Home

HP 203A User's Manual

1. 91 9 pue 91 6 lt 6 tiu o002 2 2 svia 0258 VEO POW rdv T Gv 3243 2081 U3M01103 0 s311w3 IVNDIS S3 L0N3q AT8NWZISSY SELONAG 5531 SMOTIOS SY NMOS way SATIVA 102812 ASATOV S300N3 5 SUA 32NY LOAGNI 4 3ONYLIOVAYO NI 3ONVASIS 3H GALON XSLA NOIS AG ALATA WOO BLOM S NOLLVNDIS2G ATAWESSVEAS XH IUS SNOLLVNDIS iVLLHVd 53 0 HO1VH3N39 A 5 WOISSV HLA AGI HW em ASE 21 1 I 8 28815 EDAG pZ i sip 92 2 0024 ea YBMOTIOS Ch NBII wy k 27360 2 EE y dg 62 4 HW IZU 1 Oi AS v2 M M M e a 20899 80200 AT10W3SSV HOlV1nGOowW TT mA e m um m ev NOTES 1 PARTIAL REFERENCE DESIGNATIONS ARE SHOWN PREFIX WITH ASSEMBLY OR SUBASSEMBLY
2. OPERATING AND SERVICE MANUAL MODEL 203A VARIABLE PHASE FUNCTION GENERATOR SERIALS PREFIXED 1201 4 M hb zils Copyright Hewlett Packard Company 1964 301 Loveland Colorado 80537 U S A PART 00203 99002 01760 7 Printed JULY 1973 CERTIFICATION The Hewlett Packard Company certifies that this instrument was thoroughly tested and inspected and found to meet its published specifications when it was shipped from the factory The Hewlett Packard Company further certifies that its calibration measure ments are traceable to the U S National Bureau of Standards to the extent allowed by the Bureaws calibration facility WARRANTY AND ASSISTANCE Hewlett Packard products are warranted against defects in materials and workmanship This warranty applies for one year from the date of delivery or in the case of certain major compo nents listed in the operating manual for the specified period We will repair or replace products which prove to be defective during the warranty period provided they are returned to Hewlett Packard No other warranty is expressed or implied We are not liable for consequential damages Service contracts or customer assistance agreements are available for Hewlett Packard products that require maintenance and re pair on site For any assistance contact your nearest Hewlett Packard Sales and service Office Addresses are p
3. SALONAG SAUNSHOHOIN Nt 32NY SGVUVAODId NI 39NVLIOVdY2O 32NVLISISGM 3814 CHSHIO SSHINA 85601104 SY N AOHS SAMIYA LN3NOdWOO NOLLVNDISSO 3131402 355 7805 HO ATHINSSSY NOG IVLLUVd S310N 8109 HO LB cL RD XH 3Hd N AOHS SNOILY Soe 9X Wo mn RIO KO BIAS MN eoe 50 TPs R20 es Coa 19 gt Ace erie d b L4 uS i a CN o3 o2 88 RH CIS Rog VAR R32 R37 R3I HI DIST cia ADJ qi aie 3 203A M Figure 5 15 IS FROM A2 il 14 2 9 i3 24 5 i2 TO 6 TO 6 USED 19 24 8 FROM SIBR2 6 i5V 5 10 A7 6 4 TO AS 6 3 15V 2 FROM A219 FROM A2 7 Modulator Assy A3 Component Location 8 4 86 4 SSY om3 8 09270 ANVIWOD QHYX2Vd 1123743H 5961 iH91HAdO2 94069 0 9602 HOLY INOW T3NNVHO ae omm ray 99801539 fay 3S8NOdS3H 842 05 AGI oci 6 2 osi 38 453 T oy 545 05 9 ten 2 01 e 0004 i 22 lt ogy 61M GZH AGi 13NNYHO 1
4. 023 183 vH ONY OL AGi o1 9 v1 6 ASt Oi 180 0 10 H3MOT1O3 mun icu B311IN3 isnray 219 2666 15004 33 31 OV 18069 m 1 BEEN 2156 pue 11 5 A 0131295 805 1029 50200 H3ILJIHS 3SVHd Jigvisneray iSneov 9v 4905079 prog x xD 5 0001 gi A 902 Sus 3050 95 82 or Ol 3050 asnray 62 91 08 00 041 MN e 6y J zy 10 25 St D SHY 009 i aes 9 Ai 089 ASi 2 ASi 90599 50200 AT HW3SSV Section Figure 5 13 TO Ann Loa 015 TO 51881 15V 203 38 Figure 5 13 VFO Assy A10 Component Location Model 203A 01760 3 203 2 Toaz 6 415 VOC GND S BRIO FROM Figure 5 13b Decade Module Assy Ali Component Location 22 5 12 5 21819435 91 0 Ly Assy PPLA pue ASSY pp g aandrg 09210 31noow 91 37ndowW 30voaa
5. S YuViOJId NI 32NVLIOV4 VO SINKO FONVISISaH 554182 5 401704 SY NAOHS THY SAMIYA LN3NOd WOO NOLLYNDISAG 3L3 1d WOO HLOR HO S NOLLVNOIS3Q A 18NGSSYHAS HO ATHNASSV XH NAOHS SNOLLVNDISSO 30N3H3J 3H IVLLHYd S310N NOTES 1 PARTIAL REFERENCE DESIGNATIONS ARE SHOWN PREFIX WITH ASSEMBLY OR SUBASSEMBLY DESIGNATION S OR BOTH FOR COMPLETE DESIGNATION 2 COMPONENT VALUES ARE SHOWN AS FOLLOWS UNLESS WISE NOTED RESISTANCE IN OHMS 4 CAPACITANCE IN PICOFARADS DENOTES ASSEMBLY DENOTES MAIN SIGNAL PATH DENOTES FEEDBACK PATH DENOTES SCREWDRIVER ADJUST 7 X AVERAGE VALUE SHOWN OPTIMUM VALUE SELECTED FACTORY 8 DENOTES CIRCUIT FLOATING GROUND IS FROM 5 14 0 25 113 4410 12 15 11 10 15 BIAS 18 17 e 16 na 5 C6 4 a A 16 48 Ra 2 FROM AI 6 10V RIT 203A M 198 Figure 5 11 RF Amplifier Assy 2 Component Location 61 5 28419455 Egy Assy 181145 aseug eiqeisu py 8 09 10 Assy ANVdNOD 13 33 3 48 961 1891 3402 022 li WOH AGI MEMOTIOS svig etes 150709 FIAI Ov i 1169 Ol AOt
6. 2221 2231 EB2 11 EB2721 EB3311 EB3921 4701 4711 EB4721 4731 5621 EB6811 8211 EB8221 EB 27G1 6801 MF 6C T O obd CEB obd ped CD Ra bo d RS pt NG des PO Section Table 6 2 Section VI Table 6 2 0757 0724 0757 0728 0757 0730 0757 0732 0757 0734 0757 0736 0757 0737 0757 0738 0757 0740 0757 0741 0757 0743 0757 0744 0757 0745 0757 0755 0757 0757 0757 0759 0757 0761 0757 0762 0757 0766 0757 0768 0757 0771 0757 0772 0757 0774 0757 0777 0757 1027 0757 1032 0757 1033 0757 1040 0757 1050 0758 0017 0758 0041 0761 0022 0761 0054 0764 0063 0768 0001 1200 0043 1200 0081 1205 0033 1251 0135 1251 2357 1251 0475 1251 1031 1400 0084 1410 0052 6 14 Table 6 2 Replaceable Parts Cont d 392 ohms 1 619 ohms 417 2 750 chms 1 909 ohms 1 fxd met fim fxd met fim fxd met flm fxd met flm fxd met fim fxd met fim fxd met flm fxd met fxd met fim fxd met flm fxd met fim fxd met flm fxd met flm fxd met flm fxd met fim met fim fxd met
7. 5 25 Low Pass Filter Assy 4 DC Ampl Assy A6 and Square Wave Gen ad 8 Schematic 5 25 Low Pass Filter Assy A4 and A5 Component Location 5 26 Square Wave Gen Assy A8 and A9 Component Location 5 21 5 28 Low Pass Filter Assy 5 DC Assy and Square Wave Gen Assy Schematic 5 27 5 28 Power Supply Assy 22 Component 5 29 Power Supply Assy A22 and Rectifier Assy 21 Schematic 29 Frequency Tuning Assy Mechanical 5 30 Lo se os Section Figure 1 1 and Table 1 1 Model 203A M tO Md Figure 1 1 Model 203A Variable Phase Function Generator Table 1 1 Specifications FREQUENCY RANGE 0 005 Hz to 60 kHz in seven decade ranges DIAL ACCURACY 1 of reading FREQUENCY STABILITY Within 1 including warmup drift and line voltage variations of 4107 OUTPUT WAVEFORMS Sine and square waves are available simulta neously outputs have common chassis terminal MAXIMUM OUTPUT VOLTAGE 30 volts peak to peak open circuit for sinus oidal and square waveforms OUTPUT POWER 5 volts into 600 ohms 40 mw at least 40 db continuously adjustable attenuation on all outputs Two lower ranges of 0 0005 Hz option 01 0 00005 Hz option 02 are available on Special order OUTPUT IMPEDANCE 600 ohms OUTPUT SYSTEM Direct coupled output is is
8. jd Model 203A Figure i R 4 gd F 8 1 o Fog gw ril de ai In SESS ir OO Oo Cn d Oo 01760 3 Page Model 203A Variable Phase Function Generator v ox uui ip Xo Sos 42 1 0 Front Panel Description 3 2 Operating Instructions 3 3 Circuit 4 2 Block Diagram aeanoea enea 4 5 Frequency Dial Calibration 5 2 Frequency 5 2 Sine Wave 5 4 Square Wave Check 5 4 Phase Lag Check 5 5 Phase Lag Dial Adjustment 5 10 Typical Waveforms 5 12 5 13 5 14 Chassis Top View 5 15 5 16 5 Oscillator and 9 1 Divider Assembly Ai Component Location 5 17 5 18 5 Mc Oscillator and 9 1 Divider Assembly Al Schematic 5 17 5 18 RF Amplifier Assembly A2 Component Location 5 19 RF Amplifier Assembly A2 and Adjustable Phase Shifter Assembly 25 Schematic 6 0 46s a 6s 5 19 5 19 5 19b 5 20 5 21 5 22 5 23 List of Illustrations Page Decade Module Assy A11 thru A16 Component Location 5 21 5 22 VFO Assy A10 and Decade Module Assy 11 thru A16 Schematic 5 21 5 22 Modulator Assy A3 Component Location oy xus boe qnis 5 23 5 24 Modulator Assy A3 Schematic 5 23 5 24 DC Amplifier Assy and Component Location
9. 9 Vernier provides fine frequency adjustment 6 FREQUENCY MULTIPLIER selects frequency range andin the CAL position sets up the 203A for 14 VARIABLE PHASE channel sine wave frequency dial calibration see paragraph 3 7 AMPLITUDE control provides continuously adjustable attenuation of up to 40 db 7 CAL ADJ adjust frequency dial calibration see paragraph 3 7 15 VARIABLE PHASE channel sine wave out put terminals provide a nominal 30 volts peak to peak from a 600 ohm source impedance 8 REFERENCE PHASE channel sine wave AMPLITUDE control provides continuous adjust 16 VARIABLE PHASE channel square wave able attenuation of up to 40 db AMPLITUDE control provides continuously adjustable attenuation of up to 40 db 9 REFERENCE PHASE channel sine wave output terminals provide nominal30 volts peak to peak from 600 ohm source impedance 17 VARIABLE PHASE channel square wave output terminals providea nominal30 volts peak 10 Earth Ground Me to peak froma 600 ohm source impedance Figure 3 1 Front Panel Description 3 2 01760 2 Model 203A Section Figure 3 2 PHASE 1404 D wm Ip Y QV WARIADIE FUNCTION GENERATOR 203A 1 Push LINE switch ON pilot lamp glows 4 Select the desired test signal s and connect load to OUTPUT connector s 2 The Frequency Calibra
10. fxd met fim fxd met flm 150 ohms 1 met fim fxd met fim met fim UO SIUS mum mU mmm uuu 91 Q2 Q3 32 ohms 2195 12 1 ohms 1 15 ohms 1 1 4 fxd met flm 18 2 K ohms 1 fxd met 22 1 ohms 31 fxd met 24 3 ohms 417 fxd met fim 39 2 ohms 31 fxd met fim 47 5 ohms 410 1 4 W fxd met flm 61 9 K ohms 1 fxd met flm 68 1 ohms 417 1 4 W fxd met flm 82 5 ohms 1 1 4 W 121 ohms 1 1 4 W 680 ohms 1 1 4 W 100 ohms 0 5 1 4 W 200 ohms x0 565 50 ohms 1 1 4 W 1 4 W 1 4 W 1 4 W 1 4 W fxd met 1 21 ohms 1 1 4 W 5 ohms 1 1 4 W 62 ohms 1 82 ohms 1 1 4 W 1 4 W 1 1 1 2 21 ohms 1 1 4 W fxd met fim 2 43 ohms 1 3 3 4 1 4 W 32 ohms 1 1 4 W 92 ohms 1 1 4 W 1 4W 1 4 W 1 4 W 1 4 W 1 4 W 1 4 W b 1 4 W 1 4 W 1 2 W fxd met fim 1500 ohms 5 1 2 W 91 ohms 45 1 2 W 620 ohms 45 1 W fxd met fim 330 ohms 5 1 W 620 ohms 45 2 W fxd met 1000 ohms 4107 3 W Insulator transistor mtg anodized Al plate Insulator bushing nylon Q1 Q2 Q3 Heat dissipater semiconductor A6Q5 Connector printed circuit 15 tuning fork type contacts terminal type B Connector power contacts terminal type B Connector printed circuit 6 tuning fork type contacts t
11. 2 4 1 4 20 Variable Phase Channel RF Amplifier 4 2 4 23 Reference Phase Channel RF Amplifier 4 2 4 25 Variable Frequency Oscillator cA at ees 522 4 2 4 27 Decade Modules 11 16 4 2 4 29 Decade Module 11 4 2 4 31 Decade Modules 12 through 4 3 4 33 Modulator Assembly 4 3 4 35 Modulator Driver Amplifier 4 3 4 37 Reference Phase Channel Modulator ncs Fo 4 3 4 40 Variable Phase Channel Modulator 4 3 4 42 DC Amplifier Assemblies 4 3 4 44 Reference Phase Channel DC Amplifier Assembly 4 3 Table Page 1 1 5 1 0 2 1 Checks for Incoming Inspection Specifications 2 2 5 1 Required Test Equipment 5 1 5 2 Frequency Dial Calibration 5 3 5 3 Phase 5 6 iv Model Section IV PRINCIPLES OF OPERATION Cont d 4 46 Variable Phase Channel DC Amplifier Assembly 4 48 Square Wave Amplifier Assemblies 8 and 9 gt e a o y y b a n r 4 50 Reference Phase Channel Square Wave Generator 4 52 Variable Phase Channel Square Wave Generator 4 54 DC Power Supply A21 A22 4 56 Calibrate Feature Section V MAINTENANCE Required Test Equipment Performance Checks Frequency Dial Calibra
12. 4 15 The pitype tank circuit filters out harmonic frequencies which may be present at the collector of 193 A buffer amplifier A1Q4 provides further filtering isolation and power gain The output of the 9 1 divider is a 555 kc signal and is coupled by 1 2 to A2Q1 and A2Q2 see figures 5 10 and 5 12 4 16 VARIABLE PHASE SHIFTER ASSEMBLY 4 17 The variable phase shifter assembly A25 figure 5 12 is a goniometer consisting oftwostator windings a rotor winding and associated circuits The goniometer requires two 555 kc input signals one from A2Q2 toone ofthe stator windings and the other from A2Q1 and the 90 phase shift networktothe other stator winding The output phase corresponds to the angle of the rotor winding PHASE LAG control The phase can be continuously adjusted from 0 through 360 with respect to the reference signal while maintaining a constant amplitude The adjustable phase shifter output is applied to the RF amplifier assembly A2 figure 5 12 4 18 RF AMPLIFIERS A2 4 19 The RF amplifier assembly A2 consists of two RF amplifiers A2Q3 A2Q4 and A2Q5 for the reference phase channel and A2Q6 through A2Q9 for 4 Section IV Paragraphs 4 20 to 4 30 the variable phase channel Refer to the schematic diagram figure 5 12 for circuit details 4 20 VARIABLE PHASE CHANNEL RF AMPLIFIER 4 21 The signal from the variable phase shifter is amplifiedby A2Q6 then applied to the base of 297
13. on ex tender board g Set REFERENCE PHASE AMPLITUDE for AC voltmeter reading of 4 9 vac DO NOT EXCEED 7 5 MV OUTPUT AS THER MAL CONVERTER 1 VERY EASILY DAMAGED BY EXCESSIVE INPUT VOLTAGE h Disconnect AC Voltmeter i Carefully adjust REFERENCE PHASE AM PLITUDE for a DC Voltmeter reading of 7 0 millivolts Set Model 203A MULTIPLIER switch to 1 Adjust A3R20 A3R34 for VARIABLE PHASE 50 cps adj until the DC Voltmeter reads 7 0 milli volts n Set MULTIPLIER switch to 10 Note DC Volt meter reading Set MULTIPLIER switch to Adjust A4R2 A5R2 for VARIABLE PHASE 50 ke adj until DC Voltmeter reads the same as step j Repeat steps thru q until readings at 50 eps 900 eps and 50 kc are between 6 93 and 7 07 milli volts S Repeat steps a thru r for the VARIABLE PHASE OUTPUT t Disconnect Thermal Converter and connect AC VTVM to REFERENCE PHASE OUTPUT terminals Set REFERENCE PHASE AMPLITUDE fully clockwise u Adjust A6R20 A7R20 for VARIABLE PHASE AMP Adj for 10 6 volts v Repeat steps t and u for the VARIABLE PHASE OUTPUT 3 24 PHASE LAG DIAL a Connect Model 203A as shown in figure 5 6 01760 3 fully clockwise Section V Paragraphs 5 24 to 5 29 b Set FREQUENCY dial to 10 switch to 100 MULTIPLIER Set both AMPLITUDE controls c Adjust PHASE LAG dial and one not both of the AMPLITUDE controlsfor minimum readi
14. znao 209220 ER LIO NOH 3 3 naow 9 813 11607 ao ru Ed T3 7 KIE OL j 155 1 8815 eere Fa eei aas Woes AS 0081 150707 Shia 49 30h1n9Wv n 1219 Gz 300 any 2 9 MUZE 016 2 t t 2750 IHI gis oie lt I isnray OWS 2 e M 4581 OL 8201 13 rav 431d Wy 3334308 A5 300383 O 47160 62 4rs 98 01 062 3 23 208 lt oge 51 HAS Z n 0095 ig 80 99 0200 A18W3SSYv HOLY 1250 AON300343 3 IBVIHVA T M we 9 put qgp c saandry VEO WOH 10599 20200 Ad8W3SSv 310009 399939 3 Q3A3IA s 26 2 0 2 1 1131 39 996 5 TN u344ng MADHI SALONG NMOHS XV 103138 ANTVA 9 ONDIRWN saLonaa 7771 1VNOIS NIV
15. 100 0150 0015 C fxd 2 2 pf 10 500 0140 0206 C fxd dipped mica 270 pf 5 0150 0012 C fxd cer 0 01 uf 20 1000 vdew Not assigned fxd dipped mica 820 pf 2 300 fxd cer 0 01 uf 20 1000 vdew C fxd TiOg 6 8 pf 10 500 0140 0151 0150 0012 0150 0047 See introduction this section 01760 3 6 5 Section VI Model 203A Table 6 1 Table 6 1 Reference Designation Index Cont d REFERENCE DESIGNATION STOCK NO DESCRIPTION A6Q1A 1854 0014 Transistor silicon dual NPN silicon special A6Q2 1854 0033 Transistor EIA type 2N3391 NPN silicon A6Q3 A6Q4 1853 0008 Transistor EIA type 2N3250 PNP silicon 605 1854 0039 Transistor EIA type 283053 NPN silicon 1205 0033 Heat sink semiconductor A6Q5 A6R1 0757 0762 fxd met flm 24 ohms 1 1 4 W A6R2 0757 0768 fxd met flm 47 5K ohms 1 1 4 W A6R3 0757 0755 fxd met flm 12 1K ohms 1 1 4 W A6R4 0757 0772 fxd met fim 68 1 ohms 1 1 4 W A6R5 0757 0771 fxd met fim 61 9 ohms 1 1 4 W A6R6 0757 0777 fxd met fim 121K ohms 1 1 4 W A6R7 0687 1061 fxd comp 10M ohms 10 1 2 W A6R8 2100 0094 var lin comp 50K ohms 30 1 5 W A6R9 0687 4731 fxd comp 46K ohms 10 1 2 W A6R10 0687 2721 fxd comp 2700 ohms 10 1 2 W A6R11 0687 8221 fxd comp 8200 ohms 10
16. 15V COMMON Figure 5 19b Square Wave Gen Assy 8 and A Component Location 82 6 160 5 _ 90 yy 24 Assy Ssed 702 6 8 09410 isnrav 20599 50200 33891853 34 21148 1 22 L aos T v2 0 Er 3359154 LldiWHOS 099 Ofr 48 ANVdWOD 08 2 4 11 1 3 AG 9961 402 vsns0 p v o2 o aaa ONLLVO3 4 LS0fdY BEAT 3428 TANYA 1 0 3 77 NOVGO334 S310N3d NIV S310N3G 28 358 S310N30 errr 26 T SAUNTHOUUN NI JINYLINUNI 1 SQYuYiOOId KI 4 4 7 a Ni XONY ALSIS TH 34 2 1 AN ILON ISIM SSTING SMOTIO SV NMOHS 3HY SANTVA INLAT NOLLVNDIS3O 3131402 HO4 amp 3ddi 12 HLOR HO SINOLLYNDIS2Q ATANGSSVENS ATANASSY ONAAOHS SNOLLVNDIS3G 3ONdHiA DI IVILNVd diez 5310 Su ens Ti 2 AGE 00 A O3A 3IA 335 ds A38W3SSV HOLVH3N39 3AVA AS te m 5242 ATHE
17. 4 6 Ag pa 5 8 e ASI 0002543 AS p2 waters 93 L AS vz IBY 149A fo 58 sn soN 378053 i d M 85 En 450709 4001 er wol iu CB ASI ASE L 00 2 2 ee z 6 001 942 D ibi ASI nowa D 5 YN APER zb 0200 H3 01104 Sv En AY8W3SSV uar 8894 Sv 928 ASH 3 Agi 599 A18W3SSV 20 49 c 00 5 9011295 VEO TOPON NOTES PARTIAL REFERENCE DESIGNATIONS ARE SHOWN PREFIX WITH ASSEMBLY OR SUBASSEMBLY DESIGNATION S OR BOTH FOR COMPLETE DESIGNATION 2 COMPONENT VALUES ARE SHOWN AS FOLLOWS UNLESS OTHER WISE NOTED RESISTANCE IN OHMS CAPACITANCE IN PICOFARADS INDUCTANCE IN MICROHENRYS DENOTES ASSEMBLY DENOTES MAIN SIGNAL PATH 5 DENOTES SCREWDRIVER ADJUST 6 DENOTES CIRCUIT GROUND FLOATING 15V ADJUST Q2 24 5 COLLECTOR NOT USED 5 01 NOT USED i 203A M iB EMITTER 03 35 TI5V BASE Q3 NOT USED Figure 5 21 Power Supply Assy A22 Compon
18. 6 5 To obtain replacement parts address order or inquiry io your local Hewlett Packard Field Office See Appendix B for list of office locations Identify parts by their Hewlett Packard part numbers 6 6 6 1 8 4 DESIGNATORS fuse filter Q heater QCR jack R relay RT inductor 5 meter T mechanical part TC ABBREVIATIONS inside diameter ns impregnated nsr incandescent insulation ed kilohm a 1073 on kiloycycie s 73 inductor linear taper logarithmie taper piv 3 p o milli 10 pas milliampere s 10 3 pee megacycle s 1079 megohm 3 10 6 prec metal film manufacturer mounting miero 1079 Mylar Rh nanoampere s 1079 ag normally closed 2 neon normally open Se negative positive zero sect zero temperature co Si efficient NON LISTED PARTS To obtain a part that is not listed include Instrument model number Instrument serial number Description of the part Function and location of the part plug transistor transistor diode resistor thermistor Switch transformer thermocouple n H M nanosecond 9 107 not separately replace able order by description outside diameter peak printed circuit picofarad 3 10 12 peak inverse voltage part of position a polystyrene potentiometer peak to peak precision temperature coefficient long term stability and or
19. A2Q7 and A2Q8 act as anover driven amplifier which amplifies and clips the signal applied to the base of A2Q7 this operation produces a square wave of cur rent at the collector of 298 The zero crossing of the square wave of current coincides with the zero crossing of the sine wave Signal applied to the base of A2Q7 so that the phase of the applied signal is pre Served tuned network formed by A2C24 A2C25 2 29 A2C30 A2L7 and A2T2 filters the 555 Square current waveform toa nearly pure sine wave 4 22 The output of the RF amplifier circuit which is taken across A2C30 is maintained at a constant amplitude by the level controlling circuit If the out put should increase the voltage at A2C27 increases resulting ina voltage increase at the base of A2Q9 This increase is applied to the bases of A2Q7 and A2Q8 which then conduct less average current When A2Q8 conducts less the signal at its collector de decreases and the output voltage decreases opposing the original change The result is that the amplitude of the output remains nearly constant despite vari ations in the amplitude of the input signal The out put signal is then applied to 4 in the modulator assembly A3 figure 5 16 4 23 REFERENCE PHASE CHANNEL RF AMPLIFIER 4 24 The signal present at the emitter of A2Q2 is applied to the reference phase channel RF amplifier section A2Q3 through A2Q5 This stage operates FROM VFO BP FILT
20. 0140 0145 C fxd dipped mica 22 pf 5 04062 RDMI5C220J5C 9 0140 0151 C fxd dipped mica 820 pf 2 300 vdcw 14655 9 0140 0152 C ixd mica 1000 pf 5 300 vdew 04062 DM16F102J 10 0140 0153 C fxd mica 1269 pf 4195 300 vdcw 14655 CD20F1269F 2 0140 0154 fxd dipped mica 1300 pf 45 500 vdew 14655 obd 8 0140 0156 C ixd dipped mica 1500 pf 2 300 vdew 00853 obd 13 0140 0157 fxd dipped mica 1857 pf 175 500 vdew 14655 1 0140 0161 fxd dipped mica 3932 pf 1 300 vdew 14655 2 0140 0170 fxd dipped mica 5600 pf 5 300 vdew 00853 1 0140 0176 fxd dipped mica 100 pf 42 300 vdew 00853 obd 1 0140 0178 fxd dipped mica 560 pf 2 300 vdew 00853 obd 3 0140 0182 154 dipped mica 5000 pf 2 300 vdew 00853 obd 1 0140 0192 fxd dipped mica 68 pf 35 300 vdew 00853 obd4 6 0140 0195 fxd dipped mica 130 pf 5 300 vdew 00853 obd 12 0140 0198 fxd dipped mica 200 pf 25 300 vdew 00853 obd 12 0140 0201 fxd dipped mica 12 pf 575 500 00853 1 C 0140 0204 C fxd dipped mica 47 pf 45 500 00853 obd 1 0140 0206 C fxd dipped mica 270 pf 5 500 00853 obd 2 0140 0207 C fxd dipped mica 330 pf 5 500 vdew 00853 obd 1 0140 0208 fxd dipped mica 680 5 300 vdew 00853 obd 1 0140 0217 fxd dipped mica 140 pf 22 200 vdew 14655 2 0140 0218
21. 1 2 W A3R7 0687 4711 fxd comp 470 ohms 2109 1 2 W A3R8 0687 2221 fxd comp 2200 ohms 2105 1 2 W A3R9 10 0687 4711 fxd comp 470 ohms 10 1 2 W 11 0687 1521 fxd comp 1500 ohms 4100 1 2 W A3R12 0757 0743 fxd met fim 3 32 ohms 1 1 4 W PAPA A3R13 2100 0282 var lin ww 2000 ohms 20 1 1 2 W A3R14 0157 0743 fxd met flm 1 21 ohms 1 1 4 W A3R15 0757 0745 fxd met flm 4 32K ohms 417 1 4 W A3R16 0757 0339 fxd met fim 3 01K ohms 1 1 4 W um Average value shown optimum value selected at factory See introduction to this section 6 4 01760 3 203 Section VI Table 6 1 Table 6 1 Reference Designation Index Cont d REFERENCE DESIGNATION STOCK NO DESCRIPTION A3R17 2100 0909 var comp lin 100 ohms 30 1 4 W A3R18 0757 0339 fxd met fim 3 01K ohms 1 1 4 W A3R19 0757 0761 fxd met 22 1K ohms 1 1 4 W A3R20 2100 0908 var comp lin 2K 309 1 4 W A3R21 0757 0161 fxd met flm 22 1K ohms 1 1 4 W A3R22 0757 1040 fxd met fim 50 ohms 1 1 4 W A3R23 0757 0339 fxd met flm 3 01 ohms 41 1 4 W A3R24 0757 1040 fxd met flm 50 ohms 1 1 4 A3R25 0757 0339 fxd met fim 3 01K ohms 19 1 4 W A3R26 A3R27 0687 4711 fxd comp 470 ohms 10 1 2 W A3R28 0687 1521 fxd comp 1500 ohms 1095 1 2 W A3R29 0757
22. 1 2 W A6R12 A6R13 0687 8211 fxd comp 820 ohms 10 1 2 W A6R14 6 15 0687 1011 fxd comp 100 ohms 10 1 2 W mmm A6R16 0687 1021 fxd comp 1000 ohms 2109 1 2 W A6R17 0687 4711 fxd comp 470 ohms 10 1 2 W A6R18 0699 0001 fxd comp 2 7 ohms 4107 1 2 W A6R19 0757 0766 fxd met flm 39 2K ohms 1 1 4 W A6R20 2100 0282 var lin ww 2000 ohms 20 1 1 2 W A6R21 0757 0743 fxd met flm 3 32K ohms 1 1 4 W A6R22 0757 0728 fxd met fim 619 ohms 417 1 4 W 7 00203 66504 components same 00203 66502 8 ass y square wave includes 1 thru 4 Q1 thru Q5 R1 thru R12 fxd Al elect 50 uf 10 10055 25 fxd Al elect 40 uf 15 100 50 fxd dipped mica 47 pf 5 500 vaew fxd Al elect 50 pf 10 100 25 0180 0105 0180 0050 0140 0039 0180 0105 Diode silicon 50 at 1 100 PIV 12 pf 1901 0025 9140 0029 Coil R F choke universai wound unshielded 100 uh 2 6 ohms 1854 0033 1850 0040 1854 0039 Transistor EIA type 2N3391 NPN silicon Transistor germanium Transistor EIA type 2N3053 NPN silicon 0687 1031 fxd comp 10K ohms 10 1 2 W 0687 1531 fxd comp 15K ohms 10 1 2 W 0757 0744 fxd met flm 3 92K ohms 1 1 4 0757 0740 fxd m
23. 1 4 W comp lin 100 ohms 30 1 4 W Fuse 500mA Fuse 1A Lamp incandescent 10v at 0 040 amps Switch Multiplier Switch slide Switch pushbutton Plate fluted Al Spring thrust Rear side cover 5x 11 FM Front side cover 5 11 Collar Support long res bd Pin dowell Hub dial See introduction to this section 91260 76487 99934 99934 28480 28480 56137 28480 28480 16758 01295 04713 04713 28480 86684 00872 24446 86684 03877 14099 03877 86684 03877 11711 28480 01121 11236 11236 11236 76055 76055 94154 76854 28480 28480 28480 28480 28480 28480 28480 28480 obd obd obd obd 1510 0006 1510 0007 Grade 1850 0039 1850 0040 2 297 251304 253250 5 3197 1853 0016 23708 542015 obd 2N2270 SG 817 SA783 805050 34934 114821 GD 150 2100 0094 4459160 Series 110 Series 110 Series 110 1 obd 1 obd 367 obd OO 5000 0051 5000 0637 5000 8597 5000 8599 5020 0233 5020 0241 5020 0345 5020 0630 Section VI Table 6 2 me 200 Stand tilt stainless steel rod 0 188 diam Yoke coupler for 1 4 shaft p o flexible Section VI Model 203A Table 6 2 Table 6 2 Re
24. 20 100 A1C6 0140 0201 C fxd dipped mica 12 pf 5 1 7 _ 0140 0176 fxd dipped mica 100 pf 2 A1C8 0140 0217 C fxd dipped mica 140 pf 2 1 9 0140 0151 C fxd dipped mica 820 pf 2 1 10 0150 0096 fxd cer 0 05 80 20 100 vdew 1 11 0140 0157 C fxd dipped mica 1857 pf 1 2 0140 0178 fxd dipped mica 560 pf 2 A1C13 0160 0147 fxd dipped mica 2500 pf 2 111 9140 0029 Coil F choke universal wound unshielded 100 uh 2 6 ohms A1L2 00203 86009 Coil var 1091 thru 1854 0005 Transistor ELA type 2N708 NPN silicon planar A1Q4 AIR1 2 0687 1521 fxd comp 1500 ohms 10 1 2 W AIR3 0687 2221 R fxd comp 2200 ohms 10 1 2 W 1 4 0687 5621 fxd comp 5600 ohms 2109 1 2 W 0687 1231 fxd comp 12 ohms 2109 1 2 W A1R6 0687 1031 fxd comp 10 ohms 10 1 2 W 0687 1521 fxd comp 1500 ohms 100 1 2 W 1 8 0687 4721 fxd comp 4700 ohms 10 1 2 W AIRY 0687 1031 fxd comp 10 ohms 10 1 2 W 00203 84204 Transformer tuned 172 00203 84203 Transformer tuned 1 1 0410 0009 Crystal unit quartz 5 mc 2 pins on bottom A2 00203 66506 Board ass y Amplifier includes Ci thru 31 91 thru 09 CRi thru CR4 R1 thru R15 LI thru L7 14 T2 2 1 0131 0003 var mica single sect 170 780 pf 175 vdew A2C2 0160 0217 C fxd dipped mica 2300 pf 1 2 3 0160 0174 C fxd cer
25. A11 4 30 The 4 995 Mc signalfrom the crystal oscillator is applied to the emitter of A11Q1 isolation stage and subsequently appears across the pri maryof 11 1 The Signal from AliTlisappliedto asuppressed carrier balanced modulator The 495 kc VFO signal assume TO POSITION OF MULTIPLIER SWITCH SIB TO 100 POSITION OF MULTIPLIER SWITCH 518 TO MIXER IN 2ND DECADE MODULE Al2 203A M Figure 4 1 Circuit Details 4 2 01760 3 Model 203A that the FREQUENCY dialisat 60 and the VFO signal is 495 kc is applied tothe other input of the balanced modulator Both signals are mixed and the sum and difference of these two frequencies will appear at the output The signal from the balanced modulator is passed through an LC filter network which is tuned for a band pass offrom 5 4 Mc to 5 6 which only allows the sum frequencyto pass 10 1 divider A11Q3 The 10 1 divider is similar to the 9 1 divider described in paragraph 4 9 the maindifference being that the tuned tank circuit in the 10 1 divider is adi usted so that the stage provides an exact 10 1 division of the input frequency The resultant frequency is fed to the 100 position of the FREQUENCY MULTIPLIER switch and to the mixer in the second decade module 12 4 31 DECADE MODULES A12 THROUGH A16 _ _ _ 4 32 The action within the succeeding decade mod ules is the same as that described for t
26. A22C4 0180 0039 fxd elect 100 uf 12 A22C5 0180 0050 C fxd Al elect 40 uf 15 41007 50 A22C6 0150 0096 fxd cer 0 05 ufd 80 20 100 vdew A22C7 0180 0224 fxd Al elect 10 uf 10 75 15 vdcw A22C8 0180 0105 fxd Al elect 50 uf 10 100 25 A22C9 0180 0094 fxd Al elect 100 uf 10 100 25 22 10 0150 0096 C fxd 0 05 ufd 80 26 100 vdew A22C11 0160 0127 fxd cer 1 0 uf 4207 25 A22C12 0150 0096 fxd cer 0 05 ufd 80 20 100 vdew A22C13 0180 0105 fxd Al elect 50 uf 10 41007 25 A22C14 0150 0096 C fxd 0 05 ufd 80 20 100 vdew A22C15 0180 0094 C fxd Al elect 100 10 100 25 A22CR 1902 0761 Diode breakdown EIA type 1N821 5 9 to 6 5 v A22CR2 1901 0025 Diode silicon 50 MA at 1 v 100 PIV 12 pf A22CR3 A22CR4 1901 0028 Diode silicon rectifier 400 PIV 0 75 amp A22CR5 A22Q1 1854 0039 Transistor EIA type 2N3053 NPN silicon A22Q2 thru 1850 0040 Transistor PNP germanium A22Q4 2205 1854 0039 Transistor type 2N3053 NPN silicon A22Q6 1851 0017 Transistor EIA type 2N1304 NPN germanium A22R1 A22R2 0687 4721 fxd 4700 ohms 10 1 2 A22R3 0699 0002 fxd comp 6 8 ohms 10 1 2 W A22R4 0757 0732 fxd met fim 909 ohms 1 1
27. signal f Move the 10 1 oscilloscope probe to the emit ter of Q3 Adjust L2 for eleven complete cycles in 10 of horizontal deflection h Rotate L2 slug clockwise until the waveform goes out of sync and then turn L2 counterclockwise until the waveform just comes back into sync Note the amplitude of the first pip at the bottom of the waveform Turn L2 slug counterclockwise until the amplitude of the first pip is reduced by one half 9 20 FREQUENCY DIAL ADJUSTMENT a Connect Model 203A as shown in figure 5 1 Adjust the dial to a precise setting of 6 b Set MULTIPLIER switch to 1K c Set 6 on the dial exactly on the period count of 1667 2 counts Thus the quick Calibration Feature paragraph 4 56 should bring the entire range into specifications d Check each FREQUENCY dial setting listed in table 5 2 If at any point the frequency lies outside the specified tolerance adjust 11 by carefully bend ing its outer plates until the frequency is within the given tolerance Check 6 on the dial again to be sure that it is exactly on frequency 9 21 MODULATOR A3 ADJUSTMENT a Connect DC Voltmeter to A3 12 See figure 5 15 b Adjust A3R13 for minimum DC Voltmeter reading typically between 50 and 50 millivolts c Measure voltage at 4 reading should not exceed 250 mv 5 8 Model 203A 5 22 DISTORTION a Connect Distortion Analyzer and 600 ohm 1 resistor hp 40727 0081
28. to REFERENCE PHASE OUTPUT terminals b Set FREQUENCY dial to 5 MULTIPLIER to 1K c Set PHASE LAG dial to obtain maximum dis tortion reading on Distortion Analyzer d Adjust A3R17 for minimum distortion See figure 5 15 e Connect Distortion Analyzer and 600 ohm res istor to VARIABLE PHASE OUTPUT terminals f Set PHASE LAG dial to obtain maximum distor tion reading g Adjust A3R31 for minimum distortion Note Perform steps hthru r only if distortion is greater than 64 db 0 06 below reference level These steps will reduce only excess ive eighth and tenth harmonics h Check and adjust as necessary modules A11 through 14 according to Table 5 4 In each case a 10 1 oscilloscope probe is connected to the base of Q3 and a minimum signal amplitude of 5v should be maintained for proper circuit operation Table 5 4 MAXIMUM i IF 64DB MODULE RANGE DIAL DISTORTION ADJUST 64 db 64 db gt 64 db gt 64 64 db 5 23 FREQUENCY RESPONSE a Connect DC Voltmeter toREFERENCE PHASE OUTPUT terminals b Set FREQUENCY dial to 50 MULTIPLIER to 100 and both AMPLITUDE controls fully clockwise Adjust 6 8 A7R8 for VARIABLE PHASE DC Zero Adj for minimum DC Voltmeter reading typically between 20 and 20 millivolts See figure 5217 Disconnect DC Voltmeter 01760 3 C C Model 203A Note Do not place DC Amplifiers A6 and
29. 00204 Page 6 11 Table 6 1 and Page 6 17 Table 6 2 Delete C4 C5 and thru C10 Add C4 A B 0150 0119 fxd cer 2 x 0 1uf 20 250vdcw Add C5 thrn C10 Not assigned Model 203 CHANGE 3 4 Change HP Part No 5000 8597 Side Cover to 5000 0732 Page 6 15 Table 6 2 Change HP Part No 5000 8599 Side Cover to 5000 0733 Page 6 15 Table 6 2 Change HP Part No 5060 8587 Top Cover Ass y to 5060 0739 Page 6 16 Table 6 2 Change HP Part No 5060 8711 Bottom Cover Ass y to 5060 0751 Page 6 16 Table 6 2 Change HP Part No 5060 8737 Retainer to 5060 0766 Page 6 16 Table 6 2 Change HP Part 8120 1378 Power Cord to 8120 1348 Page 6 16 Table 6 2 Change HP Part No 00203 00311 Front Panel to 00203 00211 Page 6 16 Table 6 2 Change HP Part No 00203 00313 Front Panel for OPT 001 to 00203 00213 Page 6 16 Table 6 2 Change HP Part No 00203 00314 Front Panel for OPT 002 to 00203 00214 Page 6 16 Table 6 2 Change HP Part No 0160 0378 C12 to 0140 0145 Page 6 10 Table 6 1 and Page 5 21 Figure 5 14 Appendix C
30. 0180 0056 0180 0059 0180 0094 0180 0105 0180 0114 0180 0224 0340 0086 0340 0090 0370 0025 0370 0112 0370 0160 0410 0009 0683 4715 0686 6225 9687 1011 0687 1021 0687 1031 0687 1051 0687 1061 0687 1231 0687 1521 0687 1531 0687 1821 0687 2221 0687 2231 0687 2711 0687 2721 0687 3311 0687 3921 0687 4701 0687 4711 0687 4721 0687 4731 0687 5621 0687 6811 0687 8211 0687 8221 0699 0001 0699 0002 0757 0339 0757 0715 01760 4 C ixd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd Table 6 2 Replaceable Parts Cont d TOET dipped mica 47 pf 5 300 dipped mica 2300 pf 1 cer 200 pf 10 500 vdew cer 33 pf 2 600 mylar 0 1 uf 20 600 vdew elect 100 uf 12 Al elect 40 uf 15 100 50 vdew elect 1000 uf 50 elect 10 uf 10 100 25 vdew Al elect 100 uf 10 100 25 vdew Alelect 50 uf 10 100 25 vdcw elect 4 uf 100 10 25 Al elect 10 uf 10 75 15 Insulator BP Double without locating key Insulator BP with locating key Knob amplitude and frequency vernier Knob skirted bar black for 1 4 diam shaft multiplier Knob frequency multiplier Crystal unit quartz 5 mc 2 pins on bottom R R R R R Pm EDU mmm uuu fxd fxd fxd fxd comp comp comp comp fx
31. 4 W A22R5 0757 0736 fxd met flm 1 5K ohms 1 1 4 W A22R6 0681 2231 fxd comp 22K ohms 10 1 2 W A22R7 0687 2711 fxd comp 270 ohms 109 1 2 W A22R8 0687 1821 fxd comp 1800 ohms 10 1 2 W A22R9 0757 0734 fxd met fim 1 21K ohms 1 1 4 W A22R10 0687 1011 fxd comp 100 ohms 10 1 2 W A22R11 0757 0724 fxd met flm 392 ohms 2155 1 4 W A22R12 2100 0281 var lin ww 100 ohms 320 1 1 2 W A22R13 0757 1033 fxd met fim 200 ohms 0 5 1 4 W A22R14 0757 0730 fxd met fim 750 ohms 41 1 4 W Pee Pew ea eee ee A22R15 0687 3311 fxd comp 330 ohms 10 1 2 W A22R16 _ 0687 1531 fxd comp 15K ohms 10 1 2 W A22R17 687 4721 fxd comp 4700 ohms 10 1 2 W A22R18 0687 1531 fxd comp 15K ohms 10 1 2 W A22R19 0687 1011 fxd comp 100 ohms 100 1 2 W A22R20 2100 0281 var lin ww 100 ohms 320 1 1 2 W A22R21 0757 0730 fxd met flm 750 ohms 41 1 4 W A23 A24 Not assigned A25 00203 64201 Phase shifter includes C1 thru C3 25 1 A25C2 A25C3 0130 0015 0160 3132 var 9 50 pf fxd 200 pf 10 500 0180 0056 0170 0022 Ch c2 C3 fxd elect 1000 50 fxd mylar 0 1 uf 4207 600 vdew Average value shown optimum value selected at factory See introduction to this section 01760 5 6 9 Section VI Table 6 1 REFERENCE C4 C5 C6 thru C10 CIT C12
32. A2Q8 is 1853 0016 2N3638 and is a recommended replace ment for Part No 1853 0009 2N274 If either one of these transistors is replaced with the current 2N3638 the other three should also be replaced and inductors 1 1 and L2 replaced with a 56 ohm resistor hp Part No 0687 5601 This recommended change is to improve phase stability at high temperatures CHANGE 2 Change 32and 83 to HP Part No 3101 0100 and 3101 0033 respectively Page 6 10 Table 6 1 and Page 6 15 Table 6 2 Change W1 to HP Part 8120 0078 Page 6 10 Table 6 1 and Page 6 16 Table 6 2 Miscellaneous Parts Change Change HP Part No 1251 2357 connector power to 1251 0148 Page 6 11 Table 6 1 and Page 6 14 Table 6 2 Change HP Part No 1400 0084 Body fuseholder to 1400 0110 Page 6 11 Table 6 1 and Page 6 14 Table 6 2 Add Nut retaining for 1400 0110 HP Part No 1400 0111 6 11 Table 6 1 and Page 6 14 Table 6 2 Add Knob fuseholder black for 1400 0110 HP Part No 6 11 Table 6 1 and Page 6 14 Table 6 2 Change Part 00203 00211 Panel front to 00203 00201 Page 6 11 Table 6 1 and Page 6 16 Table 6 2 Change HP Part No 00203 00212 Panel rear to 00203 00202 Page 6 11 Table 6 1 and Page 6 16 Table 6 2 Change HP Part 00203 00213 Panel front to 00203 00203 Page 6 11 Table 6 1 and Page 6 17 Table 6 2 Change HP Part No 00203 00214 Panel front to 00203
33. C13 C14 C15 51 Fi Ji J2 thru J5 R2 R3 R5 R8 R10 R11 R12 R13 R14 R15 R16 R17 51 B C 51 2 52 53 TI Wi RENCE DESIGNATION STOCK 0160 0151 0160 0151 0121 0117 0160 0378 0160 0905 0140 0225 0121 0007 2140 0058 2110 0202 2110 0312 1251 0148 0340 0086 0340 0090 1510 0006 1510 0007 9140 0231 9140 0230 9140 0115 1500 0002 5040 0212 5060 0021 5000 0637 5060 0020 5020 0233 5020 0345 5020 0641 5020 0639 5020 0630 5040 0607 1850 0038 1850 0095 0761 0054 0768 0001 0764 0063 2100 0113 0757 0728 2100 0113 0757 0728 2100 0113 0757 0728 2100 0113 0757 0728 3100 0841 0160 0170 3101 1248 3101 1234 9100 0293 8120 1348 Table 6 1 DESCRIPTION NOTE Reference Designation Index Cont d 5 fxd cer 4700pf 20 80 4000vdew fxd 4700pf 20 80 4000vdcw Not assigned var air 12 5 to 86 9 pf fxd dipped mica 27 pf 557 500 fxd cer 33 pf 2 600 fxd dipped mica 300 pf 1 var Lamp incandescent Fuse 500mA for 230V operation 300 vdew air 3 6 pf to 26 pf single sect 10 v at 0 040 amps Fuse 1A for 115V operation Connector power receptacle 3 pin male recessed chassis mou
34. FM 5020 0241 Support long res bd 5040 0619 Indicator freq dial 5060 0222 Handle ass y side 5060 0625 Ass y connector 5060 0731 Frame ass y 5x 11 FM 5060 0739 Top cover 111 FM 5060 0751 Bottom cover 111 FM 5060 0766 Retainer 5H handle 5060 0767 Foot 9211 0248 Carton corrugated 20 1 8 lg x 16 3 4 wd x 10 1 2 deep x 350 Ib test Foam poly 10 3 4 Ig x 4 wd 9223 0040 00203 00101 00203 00211 00203 00212 Chassis main Panel front Panel rear ADDITIONAL PARTS FOR 203A OPTION 01 Panel front Board decade module ADDITIONAL PARTS FOR 203A OPTION 02 Panel front Board decade module 00203 00213 00203 66501 00203 00214 00203 66501 See introduction to this section 01760 4 6 11 Section VI Model 203A Table 6 2 Table 6 2 Replaceable Parts 61B 40D 4 Plate freq dial 28480 61B 40D 4 120A 47A Spacer binding post 28480 120A 47A 0121 0007 C var air 3 6 pf to 26 pf single sect 80486 CT2 0 25L 0121 0117 C var air 12 5 to 86 9 pf 71630 882758 0130 0015 C var cer 9 50 pf 12982 3192 000 U2PO 47R 0130 0017 C var cer 8 50 pf 12982 557 019 U2PO 34R 0131 0003 C var mica single sect 170 180 pf 175 72136 T52910 vdcw 0140 0054 C fxd molded mica 10 pf 10 04062 RCM15EI01K 1
35. Square Wave Check 5 4 01760 3 Model 203 203A VARIABLE PHASE FUNCTION GENERATOR REFERENCE PHASE OUTPUT VARIABLE y PHASE OUTPUT Section V Paragraphs 5 8 to 5 9 Figure 5 5 ELECTRONIC COUNTER 523 203A M 14A Figure 5 5 Phase Lag Check 9 8 SQUARE WAVE CHECK Connect Model 203A as shown in figure 5 4 b Set instrument controls as follows Model 203A FREQUENCY 10 MULTIPLIER 44 100 UAMPLITUDE 2 both CW Oscilloscope en a e oa ED a e A DC SENSITIVITY 5 SWEEP TIME 1 MSEC CM TRIGGER SOURCE INT TRIGGER SLOPE 5 233 uo OEC c Adjust Model 203A FREQUENCY dial so that one cycle of square wave fills exactly 10 em of hori zontal deflection d Zero crossing of square wave should occur between 4 8 and 5 2 cm from start of sweep Peak to peak voltage should be at least 15 volts e Set Oscilloscope SENSITIVITY to 5v cm Ad just VERTICAL POSITION to bring first the top of the square wave into view then the bottom of the Square wave f Overshoot should not be more than 5 of the amplitude 1 5 cm 8 Set Oscilloscope SWEEP TIME to 1uSEC CM SENSITIVITY to 5 V CM 01760 2 Square wave rise time should be less than 0 2 usec from 10 to 90 points j Set Oscilloscope TRIGGER SLOPE to Square wave fall time should be less thanO 2 usec from 10 to 90 points
36. Turn L2 slug clockwise until the waveform goes out of sync Next turn L2 slug counterclock wise until the waveform just comes back into sync m Rotate the frequency dial slowly toward the high end until the waveform goes out of sync n Turn L2 slug counterclockwise until the wave form just comes back into syne o Repeat steps m and n until the waveform is synchronized while rotating the dial between the extreme tugh and low ends p Rotate the frequency dial until the first pip on the waveform is at maximum amplilude Turn 12 slug counterclockwise to reduce the amplitude of the first pip to one half the amplitude noted instepp The bottom of the first pip will he slightly low er inamplitude than any other part of the waveform 5 7 Section Paragraphs 5 19 to 5 23 and Table 5 4 5 19 MODULE 12 THROUGH 16 ADJUSTMENTS Connect the 10 1 oscilloscope probe to the of and CR2 see figure 5 13b and set the controls as follows SENSITIVITY 02v em SWEEP TIME 2 usec em TRIGGER SOURCE INT b Set the frequency dial to any position and the range switch to the 1K position The reason for this setting is that the frequency range of these decades is small Adjust and L1 for maximum 5 me signal see figure 5 7 waveform 8 d Move the 10 1 oscilloscope probe to the base of Q3 and change the vertical sensitivity to e Adjust T2 for maximum amplitude of the 5 mc
37. applied tothe base of A1Q3 and the second is a mixing action within 103 Each function occurs at 01760 2 a different time during each cycle of oscillation and together tend to synchronize A1Q3 with a sub multiple frequency of the frequency applied to the base of the divider 4 12 Divider A1Q3 operates in the region of voltage Saturation for a portion of each cycle During the saturation period the impedance betweenthe base and collector of A1Q3 becomes very low for the rest of cycle the impedance between the base and collector is relatively high The variation in impedance between base and collector of A1Q3 results in amplitude mod ulation about 10 of the signal on the base of the divider This amplitude modulation creates sidebands at the 8th and 10th harmonic of the divider oscillating frequency 4 13 The signal applied to the base of A1Q3 is about 4 995 Mc which is generated by the crystal oscillator circuit The tank circuit of the 9 1 divider is tuned so that A1Q3 is oscillating at the 9th sub multiple frequency of 4 995 Mc 555 4 14 The mixing process within A1Q3 occurs at the time during each cycle when the divider just starts to conduct During this short time the 8th and 10th harmonic of the 555 ke signal are mixed with the 9th harmonic resulting in frequency component at 555 ke which influences the oscillations of A1Q3 The result is that 193 stays synchronized to the 9th sub har monic of 4 995 Mc
38. boards 9 9 Section V Model 203A Paragraph 30 Figure 5 6 and Table 5 5 2 VARIABLE PHASE FUNCTION GENERATOR AC VOLTMETER 94038 476000 UV2W 1 2 0727 008 203A M IG Figure 5 6 Phase Lag Dial Adjustment 9 30 Observe the following rules when repairing c To remove a damaged component clip com double sided etched circuit boards ponent leads near the component then apply heat and remove each lead with a straight upward motion a Solder from the conductor side of the etched d Useaspeciaitoo to remove components having circuit board multiple connections such as potentiometers etc Refer to table 5 1 for type of soldering tip required b Avoid applying excessive heat when soldering e Use a toothpick to free hole of solder before on the circuit board installing a new component Table 5 5 Purpose of Factory Selected Values provide proper range for A2C1 Adjust only if 25 201 or A2Q2 are changed A2C2 A2CT To provide proper amplitude for 09 A25 drive To provide proper amplitude for 909 A25 drive Adjust only if A25 A2Q1 or 2Q2 are changed Adjust only if A25 A2Q1 or 2 11 A2Q2 are changed To eliminate H oscillations on the 24 5 volt de supply 5 10 01760 3 203 Section V Table 5 6 Table 5 6 Troubleshooting Summary Symptoms 1 No output on any channel 2 Output on one channel only s
39. fxd fxd NPN silicon comp 1000 chms 10 1 2 W comp 680 ohms 10 1 2 W met flm 1 5 ohms 41 1 4 W met flm 150 ohms 1 1 4 W comp 4700 ohms 4107 1 2 W met flm 100 ohms 40 50 1 4 W comp 680 ohms 41055 1 2 W met flm 1 5 ohms 417 1 4 W met 150 ohms 1 1 4 W comp 4700 ohms 10 1 2 W comp 47 ohms 10 1 2 W comp 3900 ohms 2109 1 2 W comp 47 ohms 10 1 2 W comp 10 ohms 4107 1 2 W comp 47 ohms 10 1 2 W comp 56 ohms Transformer tuned Transformer tuned See introduction to this section 6 3 Section VI 203 Table 6 1 Table 61 Reference Designation Index Cont d REFERENCE DESIGNATION STOCK DESCRIPTION 00203 66507 Board ass y modulator includes thru C20 1 thru R39 Li thru L6 1 thru T4 91 thru 913 fxd cer 0 47 uf 80 20 25 vdcw fxd TiOg 6 8 pf 10 500 fxd cer 0 47 uf 80 20 25 vdew fxd cer 0 01 uf 8095 20 100 A3C2 A3C3 A3C4 5 0160 0174 0150 0047 0160 0174 0150 0093 3 8 A3C9 fxd cer 0 47 uf 80 20 25 fxd mica 1269 pf 1 300 fxd cer 0 05 ufa 80 20 100 fxd cer 0 47 uf 80 20 25 0160 0174 0140 0153 0150 0096 0160 0174 3 10 A3C11 0150 0096 fxd cer 0 05 ufd 80 20 100 vdew 12
40. fxd comp 10K ohms 10 1 2 W 1188 0687 4721 fxd comp 4700 ohms 10 1 2 W A11R9 A11R10 118 11 0687 2221 0687 1031 0687 1051 fxd comp 2200 ohms 2105 1 2 W fxd comp 10K ohms 10 1 2 W fxd comp 1M ohms 4102 1 2 W mone woe e 11 1 A11T2 00203 84202 00203 84201 Transformer tuned Transformer tuned A12 thru A16 00203 66501 components same as A11 A17 18 Optional A19 A20 Not assigned A21 Board ass y rectifier includes Ci C2 R1 CR1 thru CR4 00203 66510 A21C1 A21C2 0130 0017 0140 0054 C var cer 8 50 fxd cer 100 pf 5 500 21 1 thru A21CR4 1901 0028 Diode silicon rectifier 400 PIV 0 75 amp A21R1 fxd met oxide flm 620 ohms 5 1 W 0761 0022 22 00203 66505 Board ass y power supply includes C1 thru C15 Q1 thru Q6 thru CR5 R1 thru R21 Not assigned C fxd 1 0 uf 20 25 vdew 0160 0127 Average value shown optimum value selected at factory See introduction to this section 6 8 01760 4 Model 203A Section VI Table 6 1 Table 6 1 Reference Designation Index Cont d REFERENCE P DESIGNATION STOCK NO DESCRIPTION sone A22C3 0180 0114 C fxd Alelect 4 uf 100 10 25 vdew
41. fxd dipped mica 160 pf 2 300 vdew 00853 obd 6 0140 0220 C fxd dipped mica 200 pf 14 300 vdew 00853 obd 1 0140 0224 fxd dipped mica 280 pf 41 300 00853 6 0140 0225 fxd dipped mica 300 pf 1 300 14655 obd 5 0150 0012 fxd cer 0 01 uf 207 1000 vdew 71590 13 Disc 0150 0015 fxd 2 2 pf gt 10 500 82142 type JM 0150 0047 fxd 6 8 pf 10 500 82142 type JM obd 0150 0069 fxd 0 001 uf 100 20 500 vdew 12982 8801 010 5001027 0150 0071 C fxd cer 400 pf 59 500 56289 19C formulation 28 0150 0093 C fxd 0 01 uf 80 20 100 vdew 91418 TA obd 0150 0096 C fxd cer 0 05 80 20 100 94145 type TA i 0150 0115 C fxd cer 27 pf 4107 500 vdew 72982 301 000 U2JO i 270K 0160 0127 fxd cer 1 0 pf 205 25 vdew 56289 5C13 0160 0147 C fxd dipped mica 2500 pf x 2 300vdew 00853 0160 0151 fxd cer 4700pf 207 80 2 4000vdew 0160 0170 fxd 0 22 pf 800 20 25vdew 56289 5C9A 0160 0174 fxd cer 0 47 80 20 25vdcw 56289 5C11A T 0160 0179 fxd dipped mica 33pf 5 0 300vdew 00853 obd Average value shown optimum value selected at factory See introduction to this section 6 12 01760 5 203 0160 0182 0160 0217 0160 3132 0160 0905 0170 0022 0180 0039 0180 0050
42. output of RF Amplifier pin 7 of 2 2 If no signal at check input pin 4 of 2 3 no signal at 2 check pins 3 and 14 of 2 4 If output is at 3 but not at 2 check components in 25 6 If no output at G no output at 2 check components listed under second symptom Defective A2Q1 or A2Q2 01760 3 Section V Model 203A Figure 5 7 1 Al 1 5 mc output 4 193 Emitter 9 2 uSEC CM 112 minimum for synchronization 5 V CM 5 pSEC CM 2 193 Base 5 A1Q3 Emitter 5 V CM 2 pSEC CM 11 2 nominal 5 V CM 5 uSEC CM 3 A1Q3 Emitter 6 A2 11 RF Amp Output A1L2 maximum for synchronization 1 V CM 1 pSEC CM 5 V CM 5 pSEC CM Figure 5 7 Typical Waveforms Page 1 of 3 9 12 01760 2 Model 203A Section V Figure 5 7 Cont d 7 A10 6 VFO Output 10 1193 Emitter 5 V CM 2 L2 maximum for synchronization 5 V CM 5 uSEC CM 8 Ail Junction CR2 11 1193 Emitter 5 V CM 1 L2 minimum for synchronization 5 V CM 5 9 A11Q3 Base 12 A11Q3 Emitter 9 V CM 2 pSEC CM L2 nominal 5 V CM 2 uSEC CM Figure 5 7 Typical Waveforms Page 2 of 3 01760 2 5 13 Section V Model 203A Figure 5 7 Cont d T ter yY T 13 1193 Emitter 16 A3 12 Modulator Output Incorre
43. x 4 Chassis main Panel front Panel rear for 115 230v operation only Panel rear for 100 v operation only Phase shifter Board ass y decade module Board ass y square wave Board ass y 5 mcps Board ass y amplifier 9140 0230 9140 0231 9140 0230 9140 0231 9211 0248 obd 9223 0040 00203 00101 00203 00211 00203 00212 00203 00216 00203 64201 9223 0040 00203 00101 00203 00211 00203 00212 00203 00216 00203 64201 00203 66501 00203 66502 00203 66503 00203 66504 00203 66505 00203 66506 00203 66507 00203 66508 00203 66510 00203 66511 00203 84201 00203 84202 00203 84203 00203 84204 00203 84205 00203 84206 00203 86001 00203 86002 Board ass y power supply Board ass y Amplifier Board ass y modulator Board ass y V F O Board ass y rectifier 00203 66510 00203 66511 00203 84201 00203 84202 00203 84203 00203 84204 Board ass y filter Transformer tuned Transformer tuned Transformer tuned Transformer tuned Transformer tuned Transformer tuned Coil var 2 5 6 2 uh Coil var 650 1100 uh 00203 86001 00203 86002 C CB qx Ra Ra See introduction to this section 6 16 01760 3 Model 203A Table 6 2 Rep
44. 0 47 uf 80 20 25 A2C4 0150 0096 fxd 0 05 ufd 80 20 100 A2C5 0160 0174 C fxd cer 0 47 uf 80 20 25 vdew A2C6 0150 6012 fxd cer 0 01 uf 20 1000 vdew A2C7 0160 0376 fxd dipped mica 68 pf 5 2 8 0160 0174 fxd 0 47 uf 805 20 25 A2C9 0150 0096 fxd cer 0 05 ufd 80 20 100 2 10 0150 0012 C fxd 0 01 uf 20 1000 2 11 0150 0145 fxd 22 pf 410 500 2 12 0150 0069 fxd 0 001 uf 100 20 500 2013 0140 0154 fxd dipped mica 1300 pf 25 2 14 0160 3132 C fxd cer 200 pf lt 10 500 vdew A2C15 0150 0096 fxd 0 05 ufd 8075 20 100 Average value shown optimum value selected at factory See introduction to this section 6 2 01760 4 Model 203 Section Table 6 1 Table 6 1 Reference Designation Index Cont d REFERENCE 5 2 C DESIGNETION DESCRIPTION NOTE A2C16 0160 0127 fxd cer 1 0 uf 420 25 A2C17 A2C18 0140 0152 C fxd mica 1000 pf 5 300 vdew A2C19 0140 0161 fxd dipped mica 3932 pf 1 A2C20 0150 0096 fxd cer 0 05 ufd 80 20 100 A2C21 0140 0178 C fxd dipped mica 560 pf 2 A2C22 0160 0174 fxd cer 0 47 uf 8095 20 25 A2C23 0150 0012 fxd 0 01 uf 2095 1000 A2C24 0140 01
45. 00 pf 42 300 A11C8 0150 0093 fxd 0 01 uf 80 20 100 vdew Average value shown optimum value selected at factory See introduction to this section 01760 5 6 7 Section VI Model 203A Table 6 1 Table 6 1 Reference Designation Index Cont d RE FE gee A11C9 0140 0224 fxd dipped mica 280 pf 1 300 A11C10 0140 0151 TS dipped mica 820 pf 2 300 vdew Al1Cli 0160 0179 fxd dipped mica 33 pf 5 300 11 12 0140 0192 fxd dipped mica 68 pf 5 300 vdew 11 13 0140 0218 fxd dipped mica 160 pf 12 300 11 14 11 15 11 16 11 17 0140 0152 0140 0154 0150 0093 0140 0195 fxd mica 1000 pf 5 300 fxd dipped mica 1300 pf 5 500 vdew fxd 0 01 uf 80 20 100 fxd dipped mica 130 pf 5 300 11 1 A11CR2 1910 0016 Diode germanium 100 at 0 85 60 working Diode silicon 30 MA at 1 v 30 2 2 ns 1901 0040 A11L1 A11L2 00203 86001 00203 86002 Coil var Coil var A11Q1 thru A11Q3 1854 0005 Transistor EIA type 2N708 NPN silicon planar 11 1 0687 1021 fxd comp 1000 ohms 10 1 2 W 1182 thru 0687 4721 fxd comp 4700 ohms 10 1 2 W 1184 11 5 1186 0757 0761 fxd met flm 22 1K ohms 417 1 4 W A11R7 0687 1031
46. 0150 0071 fxd cer 400 pf 5 500 A3C13 0180 0059 fxd elect 10 uf 10 100 25 vdew A3C14 A3C15 0140 0195 fxd dipped mica 150 pf 5 16 0150 0096 fxd 0 05 80 20 100 3C18 0150 0071 fxd cer 400 pf 595 500 A3C19 A3C20 0140 0195 ixd dipped mica 130 pf 5 thru A3L3 A3L4 9140 0137 Coil fixed F 1000 uh 5 dc current rating 135 ma Coil R F choke universal wound unshielded 100 wh 2 6 ohms Coll R F 75 uh Coil fxd R F 1000 uh 45 de current rating 135 ma 9140 0029 A3L5 A3L6 9140 0031 9140 0137 1854 0033 1 Transistor EIA type 2N3391 NPN silicon 392 A3Q3 1854 0005 Transistor EIA type 2N708 NPN silicon planar A3Q4 1854 0039 Transistor EIA type 2N3053 NPN silicon A3Q5 thru 1854 0033 Transistor EIA type 2N3391 NPN silicon A3Q8 A3Q10 thru A3Q13 1854 0039 1854 0033 Transistor EIA type 2N3053 NPN silicon Transistor type 2N3391 NPN silicon 0687 1031 fxd comp 10K ohms 4102 1 2 W A3R2 0687 1521 fxd 1500 ohms 10 1 2 W A3R3 0687 4711 fxd comp 470 ohms 10 1 2 W A3R4 0687 2221 fxd comp 2200 ohms 10 1 2 W A3R5 0683 4715 fxd comp 470 ohms 559 1 4 W 0687 4721 A3R6 fxd comp 4700 ohms 10
47. 0745 fxd met fim 4 32K ohms 1 1 4 W A3R30 0751 0339 fxd met fim 3 01K ohms 1 1 4 W A3R31 2100 0909 var comp lin 100 ohms 3075 1 4 W A3R32 0757 0339 fxd met fim 3 01K ohms 219 1 4 W A3R33 0757 0761 fxd met flm 22 ohms 1 1 4 W A3R34 2100 0908 var comp lin 2K 3076 1 4 W A3R35 0757 0761 fxd met fim 22 ohms 417 1 4 W A3R36 0757 1040 fxd met fim 50 ohms 1 1 4 W A3R37 0757 0339 fxd met fim 3 01K ohms 219 1 4 A3R38 0757 1040 fxd met flm 50 ohms 219 1 4 A3R39 0757 0339 fxd met flm 3 01K ohms 1 1 4 W_ A3T1 A3T2 4 00203 86005 Transformer driver A3T3 4 00203 86004 Transformer driver 4 00203 66511 Board 55 filter includes thru C3 R1 R2 Li thru L3 4 1 A4C2 A4C3 0140 0225 0140 0195 C fxd dipped mica 300 pf 1 300 vdew fxd dipped mica 130 pf 5 300 vdew thru A4L3 00203 86006 Coil fxd 4 5 mh A4R1 A4R2 0757 0744 2100 0282 fxd met fim 3 92 ohms 1 1 4 W var lin ww 2000 ohms 20 1 1 2 W 00203 66511 components same as 4 A6 00203 66504 Board ass y dc amplifier includes C1 thru C9 R1 thru R22 Q1 thru Q5 0150 0012 C fxd 0 01 uf 2076 1000 0150 0096 C fxd cer 0 05 ufd 80 20
48. 110 0312 2140 0058 3100 0841 3101 1234 3101 1248 5000 0051 5000 0637 5000 8597 5000 8599 5020 0233 C 5020 0241 2020 0345 5020 0630 01760 5 Table 6 2 Replaceable Parts Cont d coupler keyed and staked Coupler insulator 1 2 diam x 7 32 lg nylon Coupler hub fits 1 4 diam shaft nickel plated Binding Post black without solder turret Binding Post red without solder turret Plate mounting bakelite oval shape C1 C2 Transistor 2N301 PNP germanium Transistor PNP germanium Transistor type 2N297A power PNP germa nium Transistor EIA type 2N1304 NPN germanium Transistor EIA type 2N3250 PNP silicon Transistor PNP silicon Transistor 2N3638 PNP silicon Transistor type 2N708 NPN silicon planar Transistor silicon dual NPN silicon special Transistor EIA type 2N3391 NPN silicon Transistor EIA type 2N3053 NPN silicon Diode silicon 50 MA at 1 100 PIV 12 pf Diode silicon rectifier 200 PIV 0 5 amp Diode silicon 30 MA at 1 30 PIV 2 pf 2 ns Diode silicon rectifier 50 PIV 0 5 amp Diode pestis EIA type 1N821 5 9 to 6 5 v 0 01 C Diode germanium 100 MA at 0 85 v 60 v working var lin comp 50 ohms 30 1 5 W R var comp 2 W dual tendem var lin ww 50 ohms 1075 1 W var lin ww 100 ohms 20 1 1 2 W R lin ww 2000 ohms 22075 1 1 2 W var comp lin 2 43095
49. 54 C fxd dipped mica 1300 pf 5 A2C25 0160 3132 C fxd cer 200 pf 10 500 vdew A2C26 0150 0095 fxd cer 0 05 ufd 80 20 100 vdew A2C27 0160 0127 C fxd cer 1 0 uf 4207 25 A2C28 A2C29 0140 0152 fxd mica 1000 pf 5 300 A2C30 0140 0161 fxd dipped mica 3932 pf 1 A2C31 0180 0059 C fxd elect 10 uf 10 100 25 thru 1901 0040 Diode silicon 30 MA at 1 v 30 PIV 2 pf 2 ns A2CR4 211 9140 0037 Coil radio freq 5 mh induct universal wound A2L2 A2L3 A2L4 215 A2L6 A2L7 A2Q1 thru A2Q4 A2Q5 A2Q6 thru A2Q8 299 A2R1 A2R2 A2R3 A2RA4 A2R5 A2R6 A2R T A2R8 A2R9 A2R10 2511 A2R12 A2R13 42814 A2R15 A2R16 A2R17 2 1 A2T2 01760 4 00203 86003 9140 0037 00203 86010 1853 0016 1854 0033 1853 0016 1854 0033 0687 1021 0687 6811 0757 0736 0757 0715 0687 4721 0757 1032 0687 6311 0757 0736 0757 0715 0687 4721 0687 4731 0687 3921 0687 4701 0687 1031 0687 4731 0687 5601 00203 84205 00203 84206 AAA AAA Not assigned Coil var Coil radio freq 5 mh induct universal wound Not assigned Coil var Transistor 2N3638 PNP silicon Transistor EIA type 2N3391 NPN silicon Transistor 2N3638 PNP silicon Transistor EIA type 2N3391 fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd
50. AINTENANCE 5 1 REQUIRED TEST EQUIPMENT 9 2 Recommended test equipment for trouble shooting and performance checking is listed in table 5 1 Test instruments other than those listed may be used if their specifications equal or exceed the required characteristics 5 3 PERFORMANCE CHECKS 5 4 Use the following front panel procedures to verify proper operation of the Model 203A The Model 203A and test equipment should be operatedat 115 230 vac unless otherwise specified If the Model 203A is not within specifications at any point in this procedure refer to paragraph 5 12 ADJUST MENTS Table 5 1 Rec red Test Equipment Instrument Type Required Characteristics Voltage Range 0 50 volts Input Impedance gt 10 M ohms Accuracy 1 DC Voitmeter AC Voltmeter Oscilloscope Voltage Range Accuracy 2 Bandwidth DC 5 me Frequency Counter Range 0 005 eps 60 kc Performance Checks Distortion Analyzer Range 5 cps to 60 kc Performance Checks Model 331A Variable Transformer Output Voltage 103 127 vac 6 pin printed board extender 15 pin printed board Troubleshooting extender Adjustment Thermal 500 Converter 45 VAC input 7 0 mv DC output 0 2 9 cps 60 kc 50 watts Tip Temperature 800 F Tip Size 1 16 3 32 Round Tip Dia 3 4 Soldering Iron and Tips 01760 3 1 mv 100 v Freq Response to 600 kc 5 5 FREQUENCY DIAL CALIBRATION a Push
51. ANEOUS 61B 40D 4 Plate freq dial 120 4 Spacer binding post 0340 0090 Insulator BP with locating key 0370 0025 Knob amplitude and frequency vernier 0370 0112 Knob skirted bar black for 1 4 diam shaft multiplier 0370 0160 Knob frequency dial 1200 0043 Insulator transistor mtg anodized Alplate Q1 Q2 Q3 1200 0081 Insulator bushing nylon Q1 Q2 Q3 1251 0135 Connector printed circuit 15 tuning fork type contacts terminal type B Connector power receptacle 3 pin male 1251 2357 1251 1031 Connector printed circuit 6 tuning fork type contacts terminal 1 style d 2 thru 6 style b Connector printed circuit 6 tuning fork type contacts terminal type B 1251 0475 1400 0084 Body fuseholder 1410 0052 Bushing cal adjust potentiometer 0 435 OD x 0 438 16 1460 0114 Spring gear assembly 1490 0030 Stand tilt stainless steel rod 0 188 diam i 1500 0004 Coupler cal adjust insulator 1 2 diam x 7 32 lg nylon 1500 0005 Coupler cal adjust hub fits 1 4 diam shaft nickel plated 1510 0006 Binding Post black without solder turret 1510 0007 Binding Post red without solder turret 1520 0001 Plate mounting bakelite oval shape C1 C2 5000 0051 Plate fluted Al 5000 0732 Rear side cover 5 11 FM 5000 0733 Front side cover 5x 11
52. ASH isnray ogo Mo B M m e m npg ro 173 xzeg2 879 gt pU s 1 ihdino 3SvHd v 52 Ag 19 7 AgNI83 334 50 2000 85 9 3 88 ooze 2 E 300111971 T AGE 22 0042 ey Ol z YS Id Y 59 68 90 92 amp oly H ASE af SN ASE u3l Ji duy C CON 206998 0200 5 a Led zu 2127 ANOKA 495 Ydd zl 1 0122 i 2 5 fu 5 5 is HOES ATISW3SSY HOIVH3N39 3Hvnos S i CRS o SERPS YaMOTIOS FERSILLE 98 ASS ASI 11999 20200 AlBW3SSV 831714 5594 MO by 20999 50200 AIGWASSY H3 JidWV 9v 81 6 pue 21 5 aandra A uon eg 805 TOPON Section Figure 5 19 9 26 2 5 6 2034 5 68 OUTPUT INPUT NOT 2 E USED Figure 5 19a Low Pass Filter Assy 4 and A5 Component Location Model 203A 01760 3 FROM RS AMPLITUDE ADJUST 203 5 78 5
53. DESIGNATION S OR BOTH FOR COMPLETE DESIGNATION 2 COMPONENT VALUES ARE SHOWN AS FOLLOWS UNLESS OTHER WISE NOTED RESISTANCE IN OHMS CAPACITANCE IN PICOFARADS INDUCTANCE IN MICROHENRYS DENOTES SUBASSEMBLY DENOTES MAIN SIGNAL PATH DENOTES FEEDBACK PATH 6 DENOTES FRONT PANEL MARKING 1 DENOTES SCREWDRIVER ADJUST 8 AVERAGE VALUE SHOWN OPTIMUM VALUE SELECTED AT FACTORY 9 gt DENOTES CIRCUIT GROUND FLOATING R8 DC ZERO AD d _ 2035 AS O T NOT USED NOT USED 3 9 1 1 NOT USED NOT USED OUTPUT OUTPUT 24 5 24 54 FROM A3 5 FROM A3 H NOT USED NOT USED A6 15V 159 FROM A4 1 FROM 5 1 7 NOT USED NOT USED NOT USED NOT USED L COMMON JJ COMMON JJ COMMON COMMON 5 NOT USED NOT USED NOTE AG AND A BOARDS ARE IDENTICAL CHANGE PIN CONNECTIONS AS LISTED Figure 5 17 DC Amplifier Assy 6 and A7 Component Location 62 6 Assy gy Assy 09210 duy py Assy sseg 8179 4 ls ANVdWOS QHYWDV4 1137 3H iH91gAdQ02 050 0 vtoa i 9 88 v 5359131 LLIAHOS CN at 16 oni 0892 4M m 9 1 z1 Y G bz Hie 028 028 E
54. ER 5 4 5 6 C9 Clo amp TO MIXER IN 2ND THROUGH 6TH DECADE MODULES THE INSTRUMENT CONTAINS SIX DECADE MODULES ALL ARE IDENTICAL AND INTERCHANGEABLE Model 203A the same as the variable phase channel RF amplifier described in paragraph 4 20 The Output signal is then applied to A3T3 in the modulator assembly A3 figure 5 16 4 25 VARIABLE FREQUENCY OSCILLATOR 4 26 The variable frequency oscillator assembly A10 generates asignal thatis variable from 495 kc to 550 ke by rotation of the front panel FREQUENCY dial The FREQUENCY dial is calibrated so that with the dial set at 5 the VFO is oscillating at 550 ke and with the dialset at 60 the VFO is oscillatingat 495 output Signal from the variable frequency oscillatoris applied to the position of the MULTIPLIER ire quency range Switch andalsoto the 1st decade module Refer to the schematic diagram figure 5 14 for circuit details 4 27 DECADE MODULES 11 16 4 28 The six decade module assemblies A11 thru A16 each consist of a mixer a bandpass filter anda 10 1 divider These decades produce a band of high frequency signals that are mixed inthe modulators A3 with the 555 kc fixed frequency signal from the RF amplifiers to produce a signal in the 0 005 cps to 60 ke range refer to paragraph 1 5 for options Refer to the schematic diagram figure 5 14and figure 4 1 for circuit details 4 29 DECADE MODULE
55. GED BY EXCESSIVE INPUT h Repeat steps b thru g for VARIABLE PHASE VOLTAGE OUTPUT Set REFERENCE PHASE OUTPUT for a Disconnect resistor thermal converter and reading of 4 9 on the ac voltmeter de voltmeter d Disconnect AC Voltmeter 5 7 SINE WAVE CHECK e Slowly adjust REFERENCE PHASE OUTPUT for voltmeter reading of 7 0 millivolts a Connect Model 203A as shown in figure 5 3 01760 2 5 3 Section Model 203A Figures 5 3 and 5 4 DISTORTION ANALYZER p 331A 2 VARIABLE PHASE FUNCTION GENERATOR 9 o REFERENCE PHASE OUTPUT 205 12 1 0727 0081 AC VOLTMETER 84038 Figure 5 3 Sine Wave Check b Set Model 203 controls as follows d Using Distortion Analyzer check total har monic distortion present on signal Distortion lovel FREQUENCY 10 Should be more than 64 db 0 06 below fundamental MULTIPLIER 4499 3 35 100 frequency reference level AMPLITUDE dx both CW e Repeat step at a number of frequencies be tween 5 cps and 60 AC Voltmeter should read at least 5 3 volts f Repeat steps a through e for VARIABLE rms PHASE OUTPUT 50 MC OSCILLOSCOPE 2 VARIABLE PHASE FUNCTION GENERATOR O Ono Ke REFERENCE PROBE OUTPUT 6000 1 2W 1 0727 008 178 203 133 Figure 5 4
56. Model 203A LINE switch ON Pilot light should glow b Set FREQUENCY dial to 6 CAL PLIER switch to CAL Adjust front panel CAL until visualzero beat is obtained on front panel pilot light This occurs when flashing rate of the pilot light approaches zero MULTI d Connect Model 203A as shown in figure 5 1 e Rotate FREQUENCY dial and observe Elec tronic Counter readings at points shown in table 5 2 counter readings should be within limits shown At frequencies below 100 cps use period measurements Use Recommended Model Model 412A Performance Checks Performance Checks Model 4038 or Model 400D H L 4 Model 175A with 09 Model 1780A Hori zontal Plug In Model 1750A Verti cal Plug In t Model 10003A 10 1 Probe Model 523C Waveform Checking Performance Checks 09 5060 0651 Troubleshooting Adjustment 09 45060 00417 Frequency Response Model 11051A 8730 0016 Ungar No 776 handle with Ungar PL333 tiplet and Ungar No 885 3 4 cups tip Troubleshooting Repair 5 1 Section V Model 203A Paragraph 5 6 Figures 5 1 and 5 2 ELECTRONIC COUNTER 523C 2 VARIABLE PHASE FUNCTION GENERATOR 10 Figure 5 1 Frequency Dial Calibration This table can be used at all MULTIPLIER switch settings by changing the decimal poi
57. Q4 and A8Q5 which form a Schmitt trigger circuit The Schmitt trigger isa regenerative circuit whichchanges states abruptly when the input signal crosses specific dc triggering level The output from this stage is a square wave having a rise time of less than 0 2 microsecond with the same frequency and phase as the sine wave signal applied to the circuit The output is applied to a bridged T attenuator 4 52 VARIABLE PHASE CHANNEL SQUARE WAVE GENERATOR 4 53 The variable phase channel square wave erator operates the same as the reference phase channel described in paragraph 4 50 4 4 Model 203A 4 54 DC POWER SUPPLY 21 A22 4 55 The power supply provides regulated 15 15 and 24 5 volts and unregulated 35 volts 4 56 CALIBRATION FEATURE 4 57 A quick check for calibration of the frequency dialisa comparison between instrument and line fre quency The FREQUENCY dial is set to 6 CAL and the FREQUENCY MULTIPLIER is settothe CAL posi tion Through 51 60 cycle output from 11 is applied to the pilot light which will mix with the 60 cycle line frequency The pilot light will flicker at the difference or beat rate This rate may be adjusted to minimum by the CAL ADJ control which slightly affects the VFO frequency At a minimum rate of flicker the instrument s 60 cycle frequency will be most like the 60 cycle line frequency For checking the exact frequencies throughout t
58. ave is applied through series resistors to the emitters of the switching transistors The output at the collectors is sine wave of the sum and difference frequencies This signal is applied to the low pass filter assembly A4 figure 5 18 The filter passes only the difference frequency the output is a sine wave having a frequency that is between 0 005 Cps and 60 kc depending on the position of the FREQUENCY MULTIPLIER switch andthe FREQUENCY dial setting 01760 2 Section IV Paragraphs 4 31 to 4 51 refer to paragraph 1 5 for Options The output signal is applied to the de amplifier A6 4 39 dc reference voltage is derived by summing the signals at the collectors of A3Q5 and A3Q6 This dc reference voltage is used as a reference voltage for the differential amplifier in the dc amplifier as Sembly 4 40 VARIABLE PHASE CHANNEL MODULATOR 4 41 The variable phase channel modulator operates the same as the reference phase channel described in paragraph 4 37 except that the output is applied to the Low Pass Filter A5 and then to the dc amplifier 4 42 DC AMPLIFIER ASSEMBLIES AND A7 4 43 After passing through the low pass filter the Signal is fed to the direct coupled amplifiers A6 for the reference phase channel and A7 for the variable phase channel Refer to the schematic diagrams ures 5 18 and 5 20 for circuit details 4 44 REFERENCE PHASE CHANNEL DC AMPLIFIER ASSEMBLY 4 45 T
59. ccom plished by usingthe rack mounting kit and instructions furnished with your instrument 2 12 REPACKAGING FOR SHIPMENT 2 13 The following is general guide for repacking aninstrumentfor shipment Ifyou have any questions contact your local Sales and Service Office see lists in Appendix for location a Place instrument in original container if it is available If original container is not available can be purchased from your nearest Sales and Service Office Note If instrument is to be shipped to Hewlett Packard for service or repair attach to the instrument a tag identifying the owner and indicate the service or repair to be accomplished include the model number and full serial number of instrument In any correspondence identify the instru mentby model number and serial number prefix original container is not used b Wrap instrument in heavy paper or plastic before placing in an inner container c Useplenty of packing material around all sides of instrument and protect panel face with cardboard Strips d Place instrument and inner container heavy carton or wooden box and seal with strong tape or metal bands e Mark shipping container with Delicate Instru ment Fragile etc Section Model 203A Table 2 1 Table 2 1 Checks for Incoming Inspection Specifications Maximum Output Oscilloscope Amplitudes fully clock REFERENCE Ope
60. ct Frequency Division FREQUENCY 5 kc 5 V CM 2 8 5 V CM 1 MSEC CM 14 A8Q3 Collector 17 12 Modulator Output 5 V CM 5 pSEC CM FREQUENCY 5 9 V CM 1 5 15 A3Q5 Base 18 4894 Collector 5 FREQUENCY 1 ke 5 2 uSEC CM Figure 5 7 Typical Waveforms Page 3 of 3 5 14 01760 2 Model 203 Section Figure 5 8 ON PU Wo BOTTOM AI 203A 8S 22A Figure 5 8 Chassis Top View 01760 2 9 15 2 2 2 5 Ti5V 203 5 4 Figure 5 9 5 Me Oscillator and 9 1 Divider Assy Al Component Location 8179 1175 ey 9 5029 04 01 4 01 6 6 soxn3tg uonoeg BWY ATquassy 5209110 LOPIAIT 56 put JO e II2SO OWN 01 6 ANVdWOS QUVMNOVd LL31M3H AB 951 1HDlHAdO2 50 2 02 LM CL NM t 533418 20 GY u34Jng li tsaray SOA e 15084197 009 E ig OL Tae 008 is 0599 0200 A Z8W3JSSV H3QlAId 8019171250 9966 505 IPON ONLLVO14 47 310N3d HEV IVNDIS NIVW SH 1ON3d A18W3SSY NI
61. d comp fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd fxd comp comp comp comp comp comp comp comp comp comp comp comp comp comp comp comp comp comp comp comp comp comp met fim 3 01 ohms 417 1 4 W met flm 150 ohms 1 470 ohms 5 1 4 W 6200 ohms 45 1 2 W 100 ohms 1095 1 2 W 1000 ohms 410 1 2 W 10 ohms 2105 1 2 W 1M ohms 1095 1 2 W 10 M ohms 4107 1 2 W 12 ohms 4107 1 2 W 1500 ohms 4107 1 2 W 15 ohms 10 1 2 W 1800 ohms 1095 1 2 W 2200 ohms 1005 1 2 W 22 ohms 41075 1 2 W 270 ohms 105 1 2 W 2700 ohms 1075 1 2 W 330 ohms 2109 1 2 W 3900 ohms 1065 1 2 W 47 ohms 107 1 2 W 470 ohms 4107 1 2 W 4700 ohms 10 1 2 W 47 ohms 4107 1 2 W 5600 ohms 10 1 2 W 680 ohms 1005 1 2 W 820 ohms 10 1 2 W 8200 ohms 1095 1 2 W 2 7 ohms 10 1 2 W 6 8 ohms 10 1 2 W 1 4 See introduction to this section obd RDM20F232F3C Type CC32 TCN 200 CC20 3351 2 50 148P175A D32697 D32538 D32429 30D106G025BB4 30D107G025DH4 D34114 30 408 3025 4 30D106G015BA4 0340 0086 0340 0090 0370 0025 0370 0112 0370 0160 obd CB4715 EB 6225 EBIOLI EB1021 1031 1051 1061 1231 1521 1531 1821
62. eir reference designators and indi cates the description hp part number of each part together with any applicable notes and provides the follows a Total quantity used in the instrument TQ column b Description of the part See list of abbrevia tions below Typical manufacturer of the part in a five digit code facturers d Manufacturer s part number BT CR 25 Ag Al amp Au cer coef com comp conn cps dep DPDT DPST elect encap f FET fxd GaAs Gc gd Ge gr h Hg 01760 3 Wo dg w mn 1 og n assembly motor battery capacitor diode delay line lamp misc electronic part Silver aluminum ampere 5 gold capacitor ceramic coefficient i ob H d i og Won 1 on pn s common composition connection cycles per second deposited double pole double throw double pole single throw electrolytic encapsulated fasad s field effect transistor fixed gallium arsenide gigacycle s jot guard ed ermanium ground ed henry ies mercury 3 a M 5 3 8 2 1 See Appendix for list of manu Dupont de Nemours 6 3 Section VI Paragraphs 6 1 to 6 7 Miscellaneous parts are listed at the eud of Table 6 1 6 4 ORDERING INFORMATION
63. ent Location 62 6 4 Assy pue 09110 22 Assy 516405 722 6 AY 5 909 m 2 _ANYd OD LL3 71 434 5361 449154409 93H Pap tote saas 1 el 4 s c 41 t Zi S da 150 w 15 Te 064 itu 138 034 Baldi Id AV x 8 Nu9 n 1 yas wy 2 a di Old m T POPP FP aae sd anam YBMOTTIOS HIATOA NOliv 1081 we 531498 lt 01599 0200 50599 50200 18 3559 AlddnS 22 5 pue 12 5 amita A Veo IPPON Model 203 Section V 1590 8 169 83484 Surung Aouonboud 55 6 BUOJ 1 X 68 8 1398 249105 2000 0808 91 6 X 25 8 1195 1000 0605 SUOL 8 1 28 9 19 M T 2200 0506 LUvd du ONIHOV LIV id 01760 1 5 30 Model 203A 6 1 INTRODUCTION SECTION VI REPLACEABLE PARTS 6 2 This section contains information for ordering replacement parts Table 6 1 lists parts in alpha meric order of th
64. erminal 1 styled 2thru6 styleb Body fuseholder Bushing potentiometer 0 435 OD x 0 438 Connector printed circuit 6 tuning fork type CEB T O obd CEB T O obd CEB T O obd CEB T O obd CEB obd obd obd obd obd CEB T O obd CEB obd CEB obd CEB T O obd CEB T O obd CEB obd CEB obd CEB T O obd obd obd obd obd CEB T O obd CEB T O obd CEB T O obd CEB obd CEB T O obd CEB obd CEB obd 2 C20 C20 C32 C32 0764 0063 3MOL 1200 0043 Ne NM Pee Me ND CO mb 974 Special 1205 0033 SD 615 UR 143 006 08 109 SD 606UR TS1 1410 0052 See introduction to this section Model 203A 01760 3 5 Model 203 09 Stock No 1490 0030 1500 0002 1500 0004 1500 0005 1510 0006 1510 0007 1520 0001 1850 0038 1850 0040 1850 0095 1851 0017 1853 0008 1853 0009 1853 0016 1854 0005 1854 0014 1854 0033 1854 0039 1901 0025 1901 0026 1901 0040 1901 0049 1902 0761 1910 0016 2100 0094 2100 0113 2100 0206 2100 0281 2100 0282 2100 0908 2100 0909 2110 0202 2
65. et flm 2 21 ohms 1 1 4 W 0687 1031 fxd comp 10K ohms 2107 1 2 W fxd met fim 2 43K ohms 1 1 4 W fxd met fim 150 ohms 10 1 2W 0757 0741 0757 1050 SC Average value shown optimum value selected at factory See introduction to this section 6 6 01760 3 Model 203A Section VI Tak e 6 1 Table 6 1 Reference Designation Index Cont d REFERENCE 90 7 20 222 A8R9 2100 0206 var lin ww 50 ohms 10 1W 0758 0041 fxd met flm 91 ohms 45 1 2 W 0757 1027 fxd met flm 680 ohms 1 1 4 W 0757 0737 fxd met flm 1 62K ohms 1 1 4 W 00203 66502 All components same as A8 00203 66508 Board ass y F O includes C1 thru C12 Q1 thru Q3 R1 thru R10 10 1 0140 0156 fxd dipped mica 1500 pf 2 300 vdew A10C2 0140 0182 C fxd dipped mica 5000 pf 295 300 vdew A10C3 Not assigned 10 4 0150 0096 fxd 0 05 ufd 80 20 100 vdew A10C5 0140 0220 fxd dipped mica 200 pf 1 300 0150 0096 A10C6 fxd 0 05 ufd 80 20 100 10 7 0140 0178 fxd dipped mica 560 pf 32 300 A10C8 0150 0071 fxd cer 400 pf 5 500 vdcw A10C9 0150 0096 fxd cer 0 05 80 20 100 A10C10 0140 0153 fxd mica 1269 pf 1 300 10 11 10 12 0140 0170 0140 0217 fxd dipped
66. he dc amplifier usesa differentia amplifier for the input stage The dc reference voltage from the modulator section is used as the reference input for the differential amplifier This configuration minimizes any tendency of dc drift due to power Supply temperature variations The de amplifier circuit uses negative feedback to provide for low dis tortion amplification The output is applied to a bridged T type attenuator and the square wave gene rator 4 46 VARIABLE PHASE CHANNEL DC AMPLIFIER ASSEMBLY 4 47 The variable phase channel de amplifier oper ates the same as the reference phase channel des in paragraph 4 44 except that the output is applied to bridged T type attenuator and the square wave generator 9 4 48 SQUARE WAVE AMPLIFIER ASSEMBLIES A8 AND A9 4 49 The output sine wave from the dc amplifier is applied to a square wave generator Section 8 for the REFERENCE PHASE channel and A9 for the VARIABLE PHASE channel Refer to the schematic diagrams figures 5 18 and 5 20 for circuit details 4 50 REFERENCE PHASE CHANNEL SQUARE WAVE GENERATOR 4 51 The sine wave from the de amplifier is ampli fied by A8Q1 then applied to the base of 892 and A8Q3 act as anover drivenamplifier whichampli 4 3 Section IV Paragraphs 4 52 to 4 57 fies and clips the signal applied to the base of A8Q2 and produces a square wave at the collector of A8Q3 This square wave is applied to A8
67. he first decade module Ali The output of each module is applied to position of the FREQUENCY MULTIPLIER switch and to the mixer in the following decade module Thus a set of variable frequency signals are produced and when mixed withthe constant high frequency signal in the modulator A3 a beat frequency is produced The beat frequency is decreased bya factor of 10 for each lower range of the FREQUENCY MULTIPLIER Switch 4 33 MODULATOR ASSEMBLY 4 34 The Modulator assembly A3 consists of a mod ulator drive amplifier andtwo balanced Switching type modulators one for the REFERENCE PHASE channel andthe other for the VARIABLE PHASE channel Refer to the Schematic diagram figure 5 16 for details 4 35 MODULATOR DRIVER AMPLIFIER A M MM 4 36 The frequency selected by the FREQUENCY dial and the FREQUENCY MULTIPLIER is applied to the input of the modulator driver amplifier A3Q1 where it is amplified and applied to A3Q2 and A3Q3 A3Q2 and A3Q3 actas anoverdrivenamplifier which ampli fies and clips the signal applied to the base A3Q2 This operation produces a Square wave output at the collector of A3Q3 which is applied to the modulator section as a switching signal 4 37 REFERENCE PHASE CHANNEL MODULATOR 4 38 The modulator driving signal anddecade output is applied to the bases of the switching trans istors A3Q5 thru A3Q8 The fixed frequency a 555 sine w
68. he ranges see paragraph 5 5 Frequency Dial Calibration 01760 2 S F YIOI Zep HOLTON 1 93908 BOLTON I Jv r 93 6 49 iv 0290199 HOLVON S iv 4 0390158 ES RM P M3QrAlg 2 A 95 lt a E RE 2709210 BOivu3Na39 a5svnos oed ALI IA d vobi 4 A HAL sins 87211 y PM AE 38vHd 606 3409 01 592800 1 80 50 inaow HOLY HIN ID FATA 3uvnos 2x08 04 5 2500 Foy EA M 38306343 0 1 NOON 1 v Twa hd EPISC Mn 86865956 TIGER 5 23095 96 E amp 666 v GS PEGE TESS 105 2655 BOS 20 292666 56 lt EE HGG ion INGE EGS L 34866 965 6 95 1 M A t 10 0 BINA e 11050 4501 2W 56690 141 805 Model 203A Section V Paragraphs 5 1 to 5 5 Table 5 1 SECTION V M
69. idual continuously variable 40 db attenuators AMPLITUDE controls 1 4 The output terminals are floating with respect to ground and can be used to supply an output voltage with the common terminal grounded or can be floated up to 500 volts de above chassis ground The output impedance for all four test signal outputs is 600 ohms 1 5 OPTIONS AVAILABLE 1 6 Options 01 and 02 are available to provide two additional frequency ranges to the Model 203A Option 01 includes one additional Decade Module Board Assembly which extends the lower limit of the fre quency range from 0 005 cps to 0 0005 cps Option 02 includes two additional Decade Module Board semblies whichextendthe lowerlimitof the frequency range from 0 005 cps to 0 00005 cps These two 01760 4 options can also be installed as a field modification see Section VI for stock number of Decade Module Board Assemblies 1 7 APPLICATIONS 1 8 The Model 203A can be used for phase shift measurements vibration studies servo applications medical research distortion measurements geo physical problems subsonic and audio testing 1 9 INSTRUMENT IDENTIFICATION 1 10 Hewlett Packard uses a two sectionnine char acter 0000400000 or eight character 000 00000 or 000A00000 serial number The first three or four digits serial prefix identify a series of instrument the last five digits identify a particular instrument in that series A letter placed between
70. ine and square 3 No square wave output 4 No output on variable channel sine and square 6 Distortion on REF Sine OUT PUT varies as PHASE LAG dial is rotated Possible Cause Check VFO output at XA10 pins 4 and 6 X1K range If no output check 555 kc output XA1 pins 5 and 6 If no output at 2 check 4 995 Mc output XA1 pin 1 Check power supply voltages and continuity between circuit ground and chassis 1f output is at 2 but not at 1 check AIOLI L2 for open 10 11 C15 for short c 10 5 C8 for open If output is at 3 but not at 2 check a Open windings in AIT1 T2 or L2 b Low beta of A1Q3 04 If no output at 3 check Dand crystal Y1 transistor 101 Check output at pins 2 and 4 of XA6 or If no output check pins 12 or 4 of XA3 If output is at 2 but not e check A4 or 5 at pin 6 then pin 1 b L1 L2 or L3 might have case grounded If output is at 3 but not at pin 4 of check 399 T2 T4 for open b Misadjustment of A3R31 or R34 If output is at 8 but not at pin 12 of XA3 check AS3Q4 for open Misadjustment of A3R17 or R20 1 Check Input pin 1 of 8 or 9 2 no signal check output pin 2 of XA6 3 If signal is at 1 check output pin 6 of XA8 9 4 If signal is at 1 but not 3 check a A8Q5 Q4 or CRI for open b A9Q5 Q4 or for open 1 Check
71. laceable Parts Cont d 00203 86003 00203 86004 00203 86005 00203 86006 00203 86009 00203 86010 00203 86003 Coil var 35 80 uh 00203 86004 Transformer driver 00203 86005 Transformer driver 00203 86006 Coil fxd 4 5 mh 00203 86009 Coil var 650 1100 uh 00203 86010 Coil var 35 80 uh Additional Parts for 203A Option 01 00203 00213 00203 66501 00203 00213 00203 66501 Panel front Board decade module Additional Parts for 203A Option 02 00203 00214 00203 66501 00203 00214 00203 66501 Panel front Board decade module See introduction to this section 01760 3 M Section VI Table 6 2 6 17 Appendix C Model 203A MANUAL BACKDATING CHANGES MODEL 203A VARIABLE PHASE FUNCTION GENERATOR Manual Serial Prefixed 1201J hp Part No 00203 99002 This manual backdating sheet makes this manual applicable to earlier instru ments Instrument component values that differ from those in the manual yet are not listed in the backdating sheet should be replaced using the part number given in the manual Instrument Serial Prefix Make Manual Changes Instrument Serial Prefix Make Manual Changes 425 00770 and below 1 2 3 4 12011 02534 and below sm am 10193 and below CHANGE 1 Current Part No for Transistor A2Q3 A2Q4 A2Q7 and
72. m Repeat steps b thru k at various frequencies ranges Repeat steps a thru m for VARIABLE PHASE OUTPUT 9 9 PHASE LAG CHECK a Connect Model 203A as shown in figure 5 1 b Set instrument controls as follows Model 203A MULTIPLIER 444 145 10 FREQUENCY approximately 27 both CW Electronic Counter FUNCTION SELECTOR PERIOD STD FREQ COUNTED 1 c Adjust Model 203A FREQUENCY dial for Electronic Counter reading of 3600 d Connect Model 203A as shown in figure 5 5 e Set Electronic Counter controls as follows FUNCTION TIME INTERVAL SEP TRIGGER SLOPE both Section Paragraphs 5 10 to 5 15 Table 5 3 f Set Model 203A PHASE LAG dial to 180 g Adjust Electronic Counter TRIGGER LEVEL controls for stable reading near 1800 h Check Electronic Counter readings at 30 increments on PHASE LAG dial Readings shouldbe within the values shown in table 5 3 Table 5 3 PHASE LAG Phase Lag Check ELECTRONIC COUNTER Minimum 3550 250 550 850 21150 1450 1750 2050 2350 2650 2950 3250 5 10 INSTRUMENT COVER 5 11 remove either the top or bottom covers unscrew and remove the twocounter sunk Phillips head screws which secure the coverto the instrument Then slide the cover toward the rear of the instrument To replace the cover
73. mica 5600 pf 5 300 fxd dipped mica 140 pf 2 300 10 1 1901 0040 Diode silicon 30 MA at 1 v 30 PIV 2 pf 2 ns 1011 1012 9140 0041 9140 0029 Coil F 2 5 mh 10 Coil R F choke universal wound unshielded 100 wh 2 6 ohms 1001 1002 1003 185420033 1854 0005 Transistor ELA type 253391 NPN silicon Transistor type 2N708 NPN silicon planar 10 1 0758 0017 fxd metflm 1500 ohms 5 1 2 W A10R2 0757 0768 fxd met flm 47 5K ohms 1 1 4 W A10R3 0757 0774 fxd met flm 82 5K ohms 1 1 4 W 41084 0757 0738 fxd met fim 1 82 ohms 1 1 4 W 1085 0757 0757 fxd met flm 15K ohms 1 1 4 W A10R6 0757 0759 fxd met fim 18 2K ohms 417 1 4 W scm A10R7 0686 6225 fxd comp 6200 ohms 5 1 2 W A10R8 0757 0740 fxd met flm 2 21K ohms 219 1 4 W 1089 0687 1031 fxd comp 10K ohms 10 1 2 W A10R10 0687 1041 Not assigned A11 00203 66501 Board ass y decade module includes Cl thru C17 22201 thru Q3 thru R1 thru R11 L1 L2 T1 T2 11 1 11 2 0150 0096 fxd cer 0 05 ufd 80 20 100 vdew 11 3 0140 0145 fxd dipped mica 22 pf 5 A11C4 A11C5 0140 0198 fxd dipped mica 200 pf 5 300 vdew 11 6 11 7 0140 0156 fxd dipped mica 15
74. n Circuit Voltage wise REFERENCE PHASE 30v FREQUENCY 1 ke VARIABLE PHASE 600 Q load VARIABLE PHASE o 25 RMS 1 Frequency Range Oscilloscope ranges at low Any one output 005 cps to 60 ke DC Coupled end and high end output at all of dial points Square Wave Response Oscilloscope FREQUENCY 60 ke Rise Time DC Coupled REFERENCE PHASE u lt 200 nsec Fali Time Ampl of Overshoot lt 200 nsec lt 75 volts 5 lt 200 nsec 200 nsec lt T5 volts 5 Rise Time Fall Time Ampl of Overshoot VARIABLE PHASE Dial Accuracy Electronic FREQUENCY Any one output 1 of reading Counter ranges at least Use period two points onthe for lowfre dial quencies REFERENCE PHASE VARIABLE PHASE REFERENCE 1 Check all ranges at least three points on the dial Frequency Response Distortion 1 referenced to ike Oscilloscope Coupled Distortion Analyzer All ranges at least one point on dial RE FERENCE PHASE VARIABLE PHASE Rotate phase dial to achieve worst case 2 2 01760 1 Model 203A Section Paragraphs 3 1 to 3 10 SECTION HI OPERATION 3 1 INTRODUCTION 3 2 The Model 203A generates two sine wave and two square wave signals which are available simul tancously at the f
75. nals two re ference phase and two variable phase are available simultaneously at the OUTPUT connectors 4 4 The fixed frequency signal which is generated by a crystal oscillator is applied toboth channels and routedto a modulator through an RF Amplifier within each channel The variable frequency signal is applied directly to the modulator of each channel The fre quency of the variable frequency signal is controlled by the position of the FREQUENCY dialand the setting of the FREQUENCY MULTIPLIER switch Thesetwo Signals are mixedin the modulator and the difference frequency between the two signals is the output frequency of the Model 203A 4 5 CRYSTAL OSCILLATOR AND DIVIDER ASSEMBLY 4 6 Assembly Al consists of crystal controlled oscillator and a 9 1 frequency divider Refer to the Schematic diagram figure 5 10 for circuit details 4 7 CRYSTAL OSCILLATOR 4 8 The oscillator 1 1 A1Qi is a crystal con trolled grounded base Colpitts oscillator The 5 Mc output is applied through buffer amplifier A1Q2 for isolation to the base of the 9 1 frequency divider 4 9 9 1 FREQUENCY DIVIDER 4 10 The 9 1 divider consists of a divider A1Q3 and tank circuit which consists of 1 8 1 9 and A1L2 The divider is basically a class grounded base Colpitts oscillator 4 11 Two things occur duringeach cycle of the divi der operation One is amplitude modulation of the Signal
76. nect a 10 1 Oscilloscope probe to the junction of CR1 and CR2 seefigure 5 13b and see the controls as follows SENSITIVITY 02v cm SWEEP TIME 2 usec cm TRIGGER SOURCE INT 01760 3 Section V Paragraphs 5 16 to 5 18 b Set the frequency dial to 5 and the range Switch to 1K c Adjust T1 and L1 for maximum amplitude the 5 me signal Note Li may have two peaks The correct position of the slug is the second peak in the clockwise direction The wrong position of the slug will be noted by a sawtooth waveform d Move the 10 1 Oscilloscope probe to the base of and change the vertical sensitivity to 05v cm e Adjust T2 for maximum amplitude of the 5 mc signal f Move the 10 1 Oscilloscope probe to the emitter of Q3 g Adjust L2for eleven complete cycles in 10 of horizontaldeflection See figure 5 7 waveform 12 h Move the 10 1 Oscilloscope probe to the base of Q3 21 Rotate the frequency dial slowly to the high end The amplitude of the 5 mc signal should not fall below 1 cm 5v p p j If the signal at the high end of the dial is tc low in amplitude turn L1 slug counterclockwise until 1 em of amplitude is obtained Rotate the fre quency dial from the high end to the low end and stagger tune 1 1 and as necessary in order to maintain at least 1 cm of amplitude over the entire range k Movethe 10 1 Oscilloscope probe to the emitter of Q3 and set the frequency dial to 5 l
77. ng on AC Voltmeter Typical reading is less than 50 mv d Loosen set screws and slip PHASE LAG dial until it reads exactly 180 at the null obtained in step and then tighten the set screws Note If a phase error is noted at different points on the dial it may be necessary to slip the dial in order to minimize any errors 5 25 SQUARE WAVE A8 and A9 ADJUSTMENT a Connect DC Voltmeter to Model 203A REFER ENCE PHASE Jl OUTPUT b Set Model 203A controls as follows 10 MULTIPLIER 100 both CW c Adjust A8R9 for a minimum reading onde volt meter typically between 50 and 50 millivolts See figure 5 17 Connect de voltmeter to VARIABLE PHASE OUTPUT e Adjust A9R9 for a minimum reading on dc voltmeter typically between 50 and 50 millivolts 5 26 TROUBLESHOOTING 5 27 To locate trouble in the Model 203A start with a thorough visual inspection of the instrument Look for burned out or loose components and con nections and other similar conditions which suggest a source of trouble For further aid introubleshoot ing use Model 203A Block Diagram figure 4 1 Purpose for Factory Selected Values table 5 5 Troubleshooting Summary table 5 6 and Typical Waveforms figure 5 7 5 28 PRINTED CIRCUIT BOARD REPAIR 5 29 The Model 203 uses plated through doubles 20 Sided etched circuit
78. nt of the given t ding ounter reading INSURETHAT ALL FOUR AMPLITUDE CON TROLS ARE FULLY COUNTERCLOCKWISE 5 6 FREQUENC RESTONSE TO AVOID DAMAGE TO THE THERMAL Set Model 203A controls as follows CONVERTER i b Connect Model 203A as shown in figure 5 2 FREQUENCY 45 19 using very Short leads between the Model 203A and MULTIPLIER cm UE Us 100 Thermal Converter DC VOLTMETER 412 2 VARIABLE PHASE FUNCTION GENERATOR 5400 1 24 1 CONVERTER A THERMAL N INPUT 0 HOSIA OUTPUT BNC TO BINDING POST ADAPTER VOLTMETER 4038 203A M 1l 9 j Figure 5 2 Frequency Response 5 9 01760 2 203 Section Paragraph 5 7 Table 5 2 Table 5 2 Frequency Dial Calibration Counter Frequency Measurement above 100 cps Minimum Maximum Minimum Maximum 1980 2020 495 305 1650 1684 594 606 1415 1443 693 707 1238 1263 193 808 1100 1122 891 909 990 1010 990 1010 825 843 1188 1212 707 121 1386 1414 582 594 1683 1717 495 505 1980 2020 396 404 2475 2525 330 336 2970 3030 247 253 3960 4040 198 202 4950 5050 165 169 5940 6060 f Vary Model 203A FREQUENCY from 5 cps to g DC voltmeter reading should stay between 6 86 DO NOT EXCEED 7 5MILLIVOLT OUTPUT and 7 14 millivolts AS THE THERMAL CONVERTER IS VERY E EASILY DAMA
79. nting Insulator BP double without locating key Insulator BP with locating key Binding post black without solder turret Binding post red without solder turret Coil adjustable inductance 10 8 to 18 7 uh Coil fxd inductance 290 uh 1 Coil fxd R F Yoke coupler for 1 4 shaft 22 uh 10 o flexible coupler keyed and staked Insulator fiex coupling Gear ass y Spring thrust vernier drive Gear ass y with coupling hub Collar and stop dial hub Shaft pin dowel Shaft spur gear Bearing cap drive machine casting Hub dial Disc ass y vernier drive Transistor 2N301 PNP germanium Transistor type 2N297A power PNP germanium SG e AA Aaa es Switch fxd fxd fxd var fxd fxd var fxd var fxd fxd Switch Switch Transformer power multiplier met flm 330 ohms 45 1 W met 1000 ohms 510 3W met fim 620 ohms 457 2 W comp dual tandem 2 W met flm 619 ohms 1 1 4 W comp dual tandem 2 W met flm 619 ohms 21 1 4 W comp dual tandem 2 W met flm 619 ohms 1 comp dual tandem A W met flm 619 ohms 1 1 4 W 1 4 W cer 0 22 uf 80 20 25 vdew pushbutton slide Cable ass y power 6 10 See introduction to this section Model 203 Section VI Tabie 6 1 Table 6 1 Reference Designation Index Cont d RE FERENCE E C DESIGNATION STOCK NO DESCRIPTION MISCELL
80. olated from ground and may be operated floating up to 500 VDC DISTORTION Total harmonic distortion hum and noise gt 64 below fundamental lt 06 at maximum output FREQUENCY RESPONSE 1 referenced to 1 kHz SQUARE WAVE RESPONSE Rise and Fall Time 200 nsec Overshoot 5 at full output PHASE RANGE 0 to 360 degrees Accuracy 59 sine wave 100 square wave POWER 115 or 230 v 10 50 to 400 Hz DIMENSIONS Cabinet mount 5 1 4 high x 16 3 4 wide 11 1 2 deep 133 x 425 x 286 mm 01760 5 203 Section Paragraphs 1 1 to 1 11 SECTION 1 GENERAL INFORMATION 1 1 DESCRIPTION 1 2 The Hewlett Packard 203A Variable Phase Function Generator is a low frequency function gen erator which provides two sine wave and two square wave test signals at frequencies from 0 005 cps to 60 kc Refer to paragraph 1 5 Options Available 1 3 The four test signals are provided at the front panel OUTPUT connectors at an open circuit signal level of 30 volts peak to peak The sine wave and square wave test signals provided at the REFERENCE PHASE OUTPUT connectors are fixed in phase and provide a reference phase for the test signals at the VARIABLE PHASE OUTPUT connectors The vari able phase test Signals are continuously variable from 07 to 360 lag with respect to the phase of the refer ence test signals The amplitude of the four output Signals can be varied with indiv
81. placeable Parts Cont d Mfr Part No 5020 0639 Bearing cap drive 5020 0639 1 5020 0641 Shaft spur gear 3020 0641 i 5040 0212 Insulator flex coupling 5040 0212 1 5040 0607 Disc ass y vernier drive 5040 0607 1 5040 0619 Indicator freq dial 5040 0619 1 5060 0020 Gear ass y with coupling hub 5060 0020 1 5060 0021 Gear ass y 5060 0021 1 5060 0222 Handie ass y side 5060 0222 2 5060 0625 Ass y connector 5060 0625 1 5060 0731 Frame ass y 5 x 11 5060 0731 2 5060 0739 Top cover ass y 111 FM 5060 0739 1 5060 0751 Bottom cover 11L 5060 0751 1 5060 0766 5060 0761 8120 1348 Retainer 5H handle Foot ass y FM 5060 0766 5060 0767 Cable power 9100 0293 9140 0029 Transformer power 5080 3423 9140 0029 Coil R F choke universal wound un shielded 100 uh 2 6 ohms Coil F 75 uh Coil radio freq 5 mh induct universal wound 9140 0031 9140 0037 9140 0031 35000 15 502 9140 0041 Coil F 2 5 mh 1005 5 2500 1 9140 0115 Coil fxd F 22 uh 10 9330 32 9140 0137 Coil fxd F 1000 uh 25 de current 9220 28 rating 135 ma Coil fxd inductance 290 uh 1 Coil adjustable inductance 10 8 to 18 7 ph Carton corrugated 20 1 8 lg x 16 3 4 wd x 10 1 2 deep x 350 lb test Foam poly 10 3 4 lg
82. reverse the procedure 5 12 ADJUSTMENTS 5 13 The following test andadjustment procedures should be performed only if it has been definitely determined Y the Performance Checks given in paragraphs 5 5 thru 5 9 that the Model 203A is out of adjustment 5 14 POWER SUPPLY A22 ADJUSTMENTS Note the following adjustments with FRE QUENCY MULTIPLIER switch in X100 position a Supply Model 203A primary from Vari able Transformer 5 Set line voltage to nominal value 115 volts Connect DC Voltmeter and AC Voltmeter tc 22 5 See figure 5 21 d Adjust A22R12 15 volt adjust for DC Volt meter reading of 15 1 vde Voltmeter should read less than 1 0 mv ripple e Vary line voltage from 103 to 127 vac DC Voltmeter reading should not change more than x0 2 vdc f Connect DC and Voltmeter to A22 13 Adjust A22R20 15 volt adjust for DC Volt meter reading of 15 1 dc The AC Voltmeter should read less than 1 0 mv ripple 5 6 Model 203 h Vary line voltage from 103 to 127 vac DC Voltmeter reading should not change more than 20 2 vdc j Connect DC Voltmeter and AC Voitmeter to A22 2 k AC Voltmeter should read less than 2 0 mv ripple DC Voltmeter should read 24 5 40 5 vde Note It may be possible to bring the 24 5 voit supply into specifications by a slight adjust ment of the 15 volt adjust A22R12 15 volt supply must s
83. ront panel OUTPUT connectors The output Signal frequency is determined by the position of the FREQUENCY dial and FREQUENCY MULTI PLIER switch By the use of the PHASE LAG con trol the phase of the VARIABLE PHASE OUTPUT signals one sine wave and one square wave can be continuously adjusted from 0 to 360 with respect to the RE FERENCE PHASE OUTPUT signals The OUT terminals provide an open circuit signal level of 30 volts peak to peak The individual AMPLITUDE controls provide 40 db of attenuation for each output Signal The CAL ADJ control provides a means of cali brating the FREQUENCY dial with the line frequency 3 3 CONTROLS AND INDICATORS 3 4 Figure 3 1 describes the function of all front panel controls connectors and indicators The des cription of each component is keyed to a drawing which is included within the figure 3 5 OPERATING INSTRUCTIONS 3 6 Figure 3 2 contains operating procedures keyed to a drawing included in the figure Refer to figure 3 1forthe function of each control and paragraph 2 3 for setting the line voltage switch 01760 2 3 7 CALIBRATION FOR 60 CYCLE LINE FREQUENCY 3 8 A quick procedure for checking the calibration of the frequency dial is as follows a Set the FREQUENCY dial to 6 CAL b Set the FREQUENCY MULTIPLIER to CAL pilot light will flicker Adjustthe CAL ADJ for minimum rate of flicker Note If the flicker rate is not close to mini mum
84. rovided at the back of this manual Model 203 Index SECTION GENERAL INFORMATION SECTION Il INSTALLATION SECTION Il OPERATING INFORMATION SECTION IV PRINCIPLES OF OPERATION SECTION V MAINTENANCE SECTION REPLACEABLE PARTS 01760 1 iii Table of Contents List of Tables Section Page GENERALINFORMATION 1 1 1 1 Description Gow ae we He ae 1 1 1 5 Options Available 1 1 1 7 5 1 1 1 9 Instrument Identification 1 1 Section Page IL INSTALLATION 259 2 1 2 1 Inspection 2 1 2 3 Power Requirements 2 1 2 5 Three Conductor Power Cable 2 1 2 8 Installation 2 1 2 10 Rack Bench Installation 2 1 2 12 Repackaging for Shipment 2 1 Section Page IH OPERATION 4 ices Soave ble N 3 1 3 1 Introduction 3 1 3 3 Controls and Indicators 3 1 3 5 Operating Instructions 3 1 3 7 Calibration for 60 Cycle Line Frequency 3 1 3 9 Calibration for Line Frequencies Other Than 60 Cycles 3 1 Section Page IV PRINCIPLES OF OPERATION 4 1 4 1 Overall Description 4 1 4 5 Crystal Oscillator and Divider Assembly Al 4 3 4 1 4 7 Crystal Oseillator 4 1 4 9 9 1 Frequency Divider 4 1 4 16 Variable Phase Shifter Assembly 4 1 4 18 RF Amplifiers
85. s manual 2 3 POWER REQUIREMENTS 2 4 The Model 203A will operate from either 115 or 230 vac 50 400 Hz The instrument can be easily converted from 115 to 230 volt operation by changing the position of the slide switch located on rear panel so that the designation appearing onthe switch matches the nominal voltage of the power source 2 5 THREE CONDUCTOR POWER CABLE 2 6 protect operating personnel the National Electrical Manufacturers Association NEMA rec ommends that the instrument panel and cabinet be grounded Hewlett Packard instruments equip ped with a three conductor power cable which when plugged into an appropriate receptacle grounds the instrument The offset pin on the power cable three prong connector is the ground wire 2 7 To preserve the protection feature when oper ating the instrument from a two contact outlet use a three prong to two prong adapter and connect the green pigtail on the adapter to ground 2 8 INSTALLATION 2 9 The Model 203A is fully transistorized there fore no special cooling is required However the in Strument should not be operated where the ambient temperature exceeds 55 C 13 1 F 01760 4 2 10 INSTALLATION 2 11 Model 203A is initially shipped as bench type instrument unless ordered specifically as a rack type with plastic feet and a tilt stand in place Con versionto a rack mounted instrument be a
86. tay between 14 9 and 15 3 vde m Varyline voltage from 103 to 127 vac DC Voltmeter reading should not change more than 0 4 vdc n Connect DC Voltmeter to A22 14 p DC Voltmeter should read 35 5 Disconnect front panel shorting bar r Connect AC Voltmeterbetween chassis ground and circuit common A22 9 5 Use an insulated tuning wand to adjust A21C1 located onbottom of chassis for a minimum reading refer to figure 5 8 5 15 4 995 MC OSCILLATOR AND 9 1 DIVIDER Al ADJUSTMENT a Connect 10 1 probe of Oscilloscope to base of 103 and ground lead to ground plane of oscillator board See figure 5 9 b Set Oscilloscope controls as follows INPUT voe A e Vere e ea ners AC SENSITIVITY ox 05 V CM SWEEP TIME 2 uSEC CM c Adjust AIT1 for maximumamplitude of 5 mc signal d Move 10 1 probe to emitter of A1Q3 e Adjust A1L2 for eleven waveforms in 10 cm of horizontal deflection Adjust AlL2 so that the first pip of signal is slightly larger than the rest see fig ure 5 7 Waveforms 3 5 f Repeat steps athru e until optimum adjustment is obtained g Move probe to A1 5 Adjust 2 for maximum amplitude of 555 ke Signal 01760 3 203 5 16 ADJUSTABLE PHASE SHIFTER 25 ADJUSTMENT Note The following procedure must be performed with printed board A2 in its normal operating position in the Model 203A Do not use ex
87. tender board a Connect Voltmeter across output of Phase Shifter Assembly A25 using short unshielded leads see figure 5 8 b While rotating PHASE LAG dialthrough 3609 alternately adjust A2C1 see figure 5 11 and A25C1 until voltage levelindicated on AC Voltmeter remains with 3 of nominal signal level obtained 5 17 RF AMPLIFIER ADJUSTMENT A2 a Connect DC Voltmeter tothe collector of 293 connect 10 1 Oscilloscope probe to collector of 204 See figure 5 11 b Adjust A2L3 for maximum DC Voltmeter reading Adjust A2T1 for minimum AC voltage indication on Oscilloscope Repeat steps b and as many times neces sary for optimum adjustment Connect DC Voltmeter to collector of A2Q7 connect 10 1 Oscilloscope probe to collector of A2Q8 f Adjust A2L7 for maximum DC Voltmeter read ing Adjust A2T2 for minimum AC Voltage indication on Oscilloscope Repeat steps f and gas many timesas necessary for optimum adjustment 5 18 DECADE MODULE 11 ADJUSTMENT Note Each of the six Decade Modules A11 through 16 are electrically identical Each module Should be adjusted in the 1K position of the range switch for best results All components are referred to by their location on the mod ule Forexample L1is A11L1 21 1 A13L 1 etc depending upon the particular module under test Module All procedure is given Separately because of its wide frequency range Con
88. the two sections identifies the country where the instrument was man ufactured The serial number appears on a plate located on the rear panel All correspondence with Hewlett Packard Sales Service Offices with regard to an instrument should refer to the complete serial number 1 11 the serial prefix does not agree with the serial prefix onthe title page of this manual a Manual Changes sheet supplied will describe changes which will adapt this manual to an instrument with a differ ent serial prefix Technical corrections if any to this manual due to known errors in print are called Errata and are shown on the change sheet For in formation on manual coverage of any hp instrument contact the nearest hp Sales Service Office addresses are listed at the rear of this manual 1 1 Model 203A Section Paragraphs 2 1 to 2 13 SECTION INSTALLATION 2 1 INSPECTION 2 2 This instrument was carefully inspected both mechanically and electrically before shipment It shouldbe physically free of mars or scratches and in electrical order upon receipt To confirm this the instrument should be inspected for physical damage in transit Also checkfor supplied accesso ries and test the electrical performance of the instru ment using Table 2 1 or the procedure outlined in para graph 5 3 If there is any apparent damage file a claim with the carrier and refer to the warranty on the inside front cover of thi
89. tion Frequency Response Sine Wave Check Square Wave Check Phase Lag Check 0 Instrument Cover Removal 2 Power Supply 22 Adjustments 5 4 995 Mc Oscillator and 9 1 Divider A1 Adjustment 4 04 4 5 1 5 3 5 5 5 6 5 7 5 8 5 9 5 1 5 1 5 14 5 1 5 16 Adjustable Phase Shifter 25 Adjustment 5 17 RF Amplifier Adjustment A2 5 18 Decade Module A11 Adjustment 5 19 Decade Module 12 16 Adjustments 5 20 Frequency Dial Adjustment 5 21 Modulator A3 Adjustment 5 22 E 5 23 Frequency Response 5 24 Phase Lag Dial 5 25 Square Wave A8 and A9 Adjustment 9 5 26 Troubleshooting e 2 c3 39 s 9 28 Printed Circuit Board Repair Section VI REPLACEABLE PARTS 6 1 Introduction 5004 6425 6 4 Ordering Information 6 6 Non Listed Parts APPENDIX CODE LIST OF MANUFACTURERS B SALES AND SERVICE OFFICES C MANUAL BACKDATING CHANGES 9 4 Module A11 A14 Adjustment 9 5 Purpose of Factory Selected Values Troubleshooting Summary Index by Reference Designator Replaceable 203 Page 4 t tf 4 ey Oto Pob 1 1 C gt C o5 EA
90. tion may be compared 9 Set AMPLITUDE control s for desired signal to line frequency as described in paragraph 3 7 level 3 Set FREQUENCY dial and MULTIPLIER 6 Set PHASE LAG controlfor desired degree of Switch to desired output frequency Use vernier phase lag of the VARIABLE PHASE test signal s control on FREQUENCY dial for fine frequency with respect to the REFERENCE PHASE test adjustments signal s Figure 3 2 Operating Instructions 01760 3 3 3 Model 203 Section IV Paragraphs 4 1 to 4 19 SECTION IV PRINCIPLES OF OPERATION 4 1 OVERALL DESCRIPTION 4 2 This section describes how the Model 203A Variable Phase Function Generator operates The block diagram figure 4 2 shows the main sections and the signal flow within the Model 203A 4 3 The Model 203A is a beat frequency oscillator which by mixing two high frequency signals generates Signals in the frequency range of 0 005 cps to 60 kc to paragraph 1 5 for options One of the high frecaency signals is a fixed frequency the other is var ible The Model 203A has two signal channels RE ERENCE PHASE and VARIABLE PHASE each of waich produces a sine wave signal and a square wave signal The two channels are electrically simi lar except that the VARIABLE PHASE channel con tains a continuously adjustable phase shifting circuit which changes the phase relationship of the VARI ABLE PHASE OUTPUT with respectto the REFER ENCZ PHASE OUTPUT The four sig
91. tol erance ow mw al resistor rhodium root meas square rotary selenium section 3 silicon slide List Reference Designators and Abbreviations XDS 2 SPDT SPST Ta TiO tog tol trim TSTR Yacw var w wiy w o vacuum tube neon bulb photocell etc cable Socket lamphoider fuseholder neiwork single pole double throw single pole singie throw tantaium titanium dioxide toggle tolerance trimmer ou u ou nu onm transistor voit 5 alternating current working volt s variable direct current working volt 3 watt s with reverse working voltage without wirewound optimum value selected at factory average value shown part may be omitted no standard type num ber selected or special type 6 1 Section Model 203 Table 6 1 Table 6 1 Reference Designation Index REFERENCE en DESIGNATION STOCK NO DESCRIPTION NOTE Ai 00203 66503 Board ass y 5 meps includes Ci thru C13 Ri thru R9 1 1 L2 Ti T2 QI thru Q4 1 1 0140 0207 fxd dipped mica 330 pf 5 A1C2 0150 0096 C fxd 0 05 ufa 80 20 100 vdcw 0140 204 dipped mica 47 pf 5 4 0140 0208 fxd dipped mica 680 pf 5 1 5 0150 0095 fxd cer 0 05 80
92. use the Frequency Calibration check paragraph 5 5 When the FREQUENCY MULTIPLIER switch is in the CAL position there is no output at the REFERENCE PHASE OUTPUT connector 3 9 CALIBRATION FOR LINE FREQUENCIES OTHER THAN 60 CYCLES 3 10 Forline frequencies otherthan 60 cps the FRE QUENCY dial is set to 1 10 of the line frequency 40 to 400 eps line frequency Again the calibration is made with the front panel CAL ADJ control which is _ adjusted for minimum flicker rate of the pilot lamp For line frequencies above 600 cps the FREQUENCY dial is set to 1 30 of the line frequency 33 3 for a 1000 cps line frequency Atthe higher line frequen ciesthe flicker intensity decreases and the CAL ADJ control sensitivity increases 3 1 Section Model 203 Figure 3 1 FUNCTION GCRERATOR MGOUL 241A 1 Push ON OFF power switch 11 REFERENCE PHASE channelsquare wave AMPLITUDE control provides continuously 2 Pilot light and calibration indicator adjustable attenuation of up to 40 db 3 Not Assigned 12 REFERENCE PHASE channel square wave output terminals provide nominal30 volts peak 4 FREQUENCY selector dial indicates to peak from a 600 ohm source impedance times the FREQUENCY MULTIPLIER switch setting 13 PHASE LAG control provides continuously adjustable phase lag from 07 through 360 of the variable phase channel with respect to the refer ence phase channel

HP 203A User's Manual

Contents

Download Pdf Manuals

Related Search

Related Contents