Potomac Valley Radio Club Newsletter May 2007
Contents
1. t be described here Instead Mike describes his use of the Mount In my case a 1 4 thick rectangular 10 X8 piece of aluminum was used to hold the arm a 2 dia X 24 pipe to the mast Only two muffler clamps were used to hold both the rectangular plate to the mast and the arm to the rectangular plate The plate at the end of the arm was the 4 element SteppIR s boom to mast plate Neither the rectangular plate or the SteppIR s boom to mast plate was pinned This was because the SteppIR was mounted to the mast after it was built on the top of the 130 foot guyed tower Also the same reason for using muffler clamps instead of conventional mast clamps U bolts and saddles None of the dimensions are critical and the PVRC Mount construction depends on the mast and boom sizes plus the material you have available Again the antenna was assembled on the tower and once completed on the end of the PVRC Mount then permanently mounted to the mast The gin pole rope was attached to the antenna while the antenna was still on the arm The antenna s boom to mast plate was disconnected from the Mount A gin pole let the ground crew do the heavy lifting was used to raise the antenna off the PVRC Mount s arm the PVRC Mount removed from the mast and the antenna mounted to the mast The PVRC Mount was used again lower on the tower to build the second 4 element SteppIR antenna at the 100 ft level If you are planning on leaving the PVRC Mount in2. 7 PVRC Net The Unofficial Contesters and Friends Net Jim WX3B originally from the PVRC email reflector Have you heard of PVRC Net Yet We have a laid back spontaneous Net that has been gathering some steam the past few weeks There is no set time or day however it generally unfolds at about 9 00pm or later on about 3 778 Contesters and friends from all over the US are starting to join us Some truly RARE DX has joined in including W3UR 3 695 night K3MM NK7U K9HMB K9ZO KA9FOX W4MYA NN3W N3ST NY3A AK3Z WT3Q KM9M K3LP N3KS W4TMN NI1N WM3O NF4A NN4N NA2P and many others that I ve missed The only consistent thing about our group is that we have the letters PVRC in the spot comments when we are putting folks out on the cluster Since many of us have time off around the holidays I expect this group to be gathering more regularly in the next two weeks so watch the cluster and join in the fun It is open to all especially if you have an interest in contesting The format for the net is Well a contester s format If you have something to say say it and hope you re loud enough to get over everybody else It is NOT a round table There is no order or check in process 73 hope to hear you on the air May Visit to Washington by Elvin JA3CZY Jim WX3B from the PVRC email reflector Dear PVRC World War II Airplane Enthusiasts Elvin JA3CZY whom mo
3. As the receiver is all solid state very little hear is generated when in operation with the result that frequency drift appears to be very low This is especially true when operated on batteries I was able to listen to a 20 meter SSB pileup for a considerable period without the need to make any tuning adjustments which is a severe test for a radio of this type that lacks synthesized local oscillators What is perhaps most impressive about the Model 339 Chinese military receiver is its construction The chassis is a large casting to which all else is attached including the front panel and the trays that contain the printed circuit boards continued on the next page 6 Chinese Military HF Receiver cont Figure 3 above shows a view of the radio removed from its case from the top while figure 4 below shows the bottom with a cover plate removed The tuning coils for the six bands are assembled in a large rotating turret that can be seen in these photos This turret stretches almost the enter depth of the receiver and brings each required coil set to the two RF amplifier stages the mixer and the local oscillator via a set of spring fingers This is a neat arrangement as it provides a short path between the active and passive portions of these stages Openings in the turret permit tuning adjustments to be made on the coil set that is in use The receiver incorporates a good deal of shielding for stability and RF immunity A set of easily
4. Congratulations also go to the NCCC and their leader Dean Straw N6BV for their excellent high road sportsmanship and competition and the job they did spotting everyone in this contest Both the PVRC and NCCC are the winners the level of competition and sportsmanship displayed by both clubs raised the playing field all 2006 ARRL Sweepstakes participants Do we have what it takes to win it in 2007 You can can be sure a much bigger and better effort will have to be waged in order to do so I m in for another great SS shootout are you The just completed Swains Island N8S DXpedition was in my opinion one of the best run events in recent DXpedition history They were on ALL the bands usually quite loud and managed over 117 000 QSOs PVRC member David K3LP was on of the co leaders of that excellent DXpedition After N8S he was heard making thousands of QSOs as NH8 K3LP on American Samoa and then from the battleship U S S Missouri as KH6BB As the Newsletter goes to press the BS7H team at Scarborough Reef has just gotten on the air Information on that DXpedition with 9V1YC and OH2BH on board can be found on the web Best wishes to everyone in working this rare DXCC entity 73 Jim WX3B Editor s Note Eric W3DQ I trust everyone has made it through the contest seasons and the sometimes painful reading of the official published results This issue was put together at the Visalia DXConvention where there w
5. Yaesu FT 1000D s n 5D430050 was purchased from an estate sale I was informed that it was recently re aligned just prior the owner became a SK To verify its performance I used it in both the phone and cw CQWW 2006 and 2007 ARRL DX contests and it performed very well Cosmetically the radio has a few very minor scratches on the upper portion of the front panel The price includes a Yaesu MD 1 Desk Microphone the operations manual and complete service manual Packing shipping amp insurance is extra and is not included in the selling price I would prefer the buyer pick it up If the travel distance is 150 miles or less we could possibly meet half way Price 1900 Call or email me directly 302 645 5664 rdrevo comcast net Packaging QSLs Foiling Mail Theft Steve Runyon WQ5G via the DX QSL email list Here s an approach for the really tough ones Use a large envelope or better yet a legal size manila envelope It will cost some extra for postage but in the end may perhaps be cheaper than having to send many requests TYPE the destination address and NO don t put the call sign For a return address make up a name of some legal firm etc somebody likely to send uninteresting and unprofitable mail overseas personally I like the firm of Dewey Cheatham and Howe attorneys at law A nice touch might be to have a stamp made up that says Legal Documents Inside
6. accessed terminals at the bottom of the radio affords test points for the later stages of the radio When first received the radio did not work There was little noise in the headphones even with all the gain controls fully clockwise and injecting a large HF signal produced no observable output I began tracing the signal path by injecting an audio signal at the AF gain control to establish that the audio stages were working and then proceeded to the 465 KHz IF stages At some point in this process the radio came alive I suspect that the wiper in one of the gain controls was not initially making contact but after repeated adjustments did so At this point amplitude modulated signals as small as 1 volt could readily be detected On the air tests showed that the radio was indeed working well I lack the facilities to perform advanced tests e g of the dynamic range or immunity or adjacent channel interference but judging from the design doubt that these are up to the best of modern standards Nevertheless considering its 1979 vintage believe that in its day this receiver was a very respectable performer It was interesting to see what a rather isolated China of that time was capable of producing It is possible of course that Chinese products were influenced by Russian imports but I have no insight as to that conjecture For Sale Yaesu FT 1000D Dick Drevo W3GNQ
7. down to 465 KHz This second mixer is followed by the crystal filters that set the receiver bandwidth see above There are two stages of gain at 465 KHz before the detector where the BFO signal can be introduced via an emitter follower that drives one end of the IF transformer secondary The output of the detector is applied to the AF gain control and filtered to generate AVC Following the AF gain control are three stages of audio gain into a push pull output stage that drives the headphones via a matching transformer The mains power supply employs a stepdown transformer bi phase rectifier arrangement and voltage stabilizer circuit to deliver the needed 12 volts DC to the radio A switch on the mains input is used to select a tap on the transformer primary for 110 volt operation in place of 220 volts A separate secondary winding on the transformer provides 3 volts AC for the pilot light The battery pack is arranged so that eight of the ten D cells are connected in series to provide the 12 volts while the remaining two deliver 3 volts for the pilot light The receiver is obviously designed to be quite sensitive and listening tests support this The radio appears to have been tested at the factory for the input signal level needed to provide a 10dB signal to noise ratio at a large number of different frequencies with the results recorded in the test manual These range from 2 6 volts at the low frequency end to 5 6 volts at 30MHz
8. place with your antenna then saddles should be used under each of the U bolts seen in the picture This will go a long way to keep the antenna and the boom to mast mount and PVRC Mount from turning This mount has the pins for permanent mounting of the antenna at the end of the arm Two great On line Resources Scott Robbins W4PA world class contester and Product Manager for Ten Tec s Amateur Radio division a has a great Blog where he talks about the trials and travails of the mix of home life amateur radio and work Those Damn Contesters Have Ruined Ham Radio http w4pa journalspace com VHF amp UHF Contesting Jamie NS3T I hope some many of you had time to join the three Spring Sprint events in April on 2 meters 222 and 432 There are two more Sprints in the coming weeks to use as tune ups for the summer contest season The Microwave 902 and up Sprint is from 6 am to 1 pm local time on Saturday May 5th The 6 meter Sprint starts at 2200z on Saturday May 12 and lasts 4 hours This is the one Sprint that starts at the same time for everyone The mults in the Spring Sprints are grid squares he new contest sponsors W4SHG and K9JK would like you to use a six character grid square locator for the contest exchange e g FM19ka Check out the rules at http www sysadnet com vhfsprintrules htm that page includes a very handy link to a map that can help you identify your six chara
9. the directions to enter the site open to all Look up roster for the complete list of members active within the YCCC The following special calls will be active during the New England QSO Party this weekend to help kick the activity off They will not be signing 30 for this particular event as many may be mobile already signing county Check http www neqp org for full details of this big operating event K1C N1C N1E N1Y All QSO s with YCCCers should be completed by December 31 2007 request for the certificate should be submitted no later than February 1 2008 QSL s may be sent to David Arruzza W1CTN 32 Benz Street Ansonia CT 06401 Also for those attending the Dayton Hamvention watch for the special YCCC 30th badges members will be wearing and congratulate them when you see them 2007 Hamfest Schedule Glenn K3SWZ Date Location May 6 Hagerstown MD Warminster PA May 12 Fredericksburg PA May 19 Sussex DE May 27 Howard County MD June 3 Manassas VA June 9 Bloomsburg PA June 17 Frederick MD July 1 Wilkes Barre PA July 4 Harrisburg PA July 15 Kimberton PA July 22 Howard County MD August 5 Berryville VA August 12 Matamoras PA August 19 Westminster MD Pleasant Hill PA September 8 Stroudsburg PA September 30 Wrightstown PA October 6 Brownstown PA October 7 Howard County MD October 21 Sellersville PA October 28 Westminster MD Updates additions correcti
10. 1 Editor s Note Potomac Valley Radio Club Newsletter May 2007 Visit us on the web at www pvrc org and www pvrcnc org _______________________________________________________ From The President Jim WX3B With just weeks to go before our annual visit to Dayton I can hear the plans of PVRC members taking shape I am pleased too report that I ll be making a brief appearance at the contester s dinner on Saturday evening and afterwards at the Crowne Plaza Super Suite It s always fun talking in person to fellow contesters I ll have a sign in sheet for PVRC members who wish to be recognized for attending If I accidentally omit you please let me know gently after I post our meeting minutes on the PVRC e mail reflector While the margin of victory may have been slim I m delighted that PVRC Took the Gavel the 1 position in the Unlimited Club category in the 2006 ARRL Sweepstakes Competition A hearty thank you goes out to ALL who participated and especially to Ty K3MM who was instrumental in organizing the effort and all the Chapter leaders who participated in the recruitment effort We had station hosts opening up their stations for the weekend and of course operators lots of them filling those chairs We had folks working behind the scenes to fix equipment repair often turning around amplifiers in very short order In the end the old axiom the club with the most entries wins held true
11. L Meetings are held on the third Tuesday of each month at the City Buffet 1306 W Patrick Street Frederick MD 301 360 9666 It s in a small shopping center Most arrive about 6 PM for dinner and informal discussions The meeting begins at 7 00 PM gt From W Patrick Street turn up McCain Dr the Mountain View Diner is on the corner then turn right into the shopping center then turn left and search for a parking place The City Buffet is tucked back in the left corner of the shopping center behind the Mountain View Diner You can t see the City Buffet from W Patrick Street The Annapolis Crew de Bob W9GE Meetings are held on the 4th Wednesday of each month at Griffens West in Annapolis We gather at about 5 30 PM and order dinner about 6 We break up usually before 8 PM E Mail W9GE to be put on the e mail reminder list PVRCNC East de Jim K4QPL We meet on the first Thursday of each month Details are always available on the web site http pvrcnc org Note The May PVRCNC meeting on May 3rd will be a joint East West meeting to be held at a midway location to be advised Probably in the Burlington area This will be an opportunity for all NC PVRC ers to get together meet new members and eyeball with old friends and competitors Highlight of the meeting will be video and pictures from the recent ARRLDX SSB Antigua dxpedition by Henry W2DZO V26H and Robert KG4NEP V26RW operating M S as V26H PVRC NC West de Tom N4IOZ T
12. adio that lacks a product detector one turns up the audio frequency gain reduces the RF gain and carefully adjusts the BFO to make the SSB signal intelligible Range changing in the radio is performed by rotating a massive coil turret and this step changes a window in front of a metal disc that displays the frequency markings The window moves upward as the frequency is advanced and the markings are at 10 KHz intervals on the lowest frequency band rising to 50 KHz on the highest Tuning is via the large round knob in the left center of the panel Figure 2 which drives a four gang variable capacitor via a smooth gear reduction assembly The top right hand switch Figure 2 above the band change knob turns on the BFO or in a third position grounds the antenna input and turns on a 500 KHz crystal calibrator that is coupled in to the front of the receiver The bottom right hand control is the AF gain while concentric controls on the opposite side govern the RF gain separately of the RF and IF stages To the left of the AF gain control is a knob that adjusts an aerial peaking capacitor for best match Beneath the meter is the BFO control which appears variable over 3 0 KHz To the right of the meter is an IF bandwidth control bandwidths of 6 0 3 0 1 0 and 0 4 KHz are offered These different bandwidths are selected by changing crystal filters in the first 465 KHz IF stage The meter normally functions as an uncalibrated S mete
13. as a noticeable PVRC and NCCC presence This issue contains excellent contributions and features from you our talented and insightful members I believe we ve reached a size limit for emailing these newsletters to many of our members who do not have broadband connections So we re considering two versions one sent via email without photos and a second one with photos that will reside on the PVRC website Thoughts Last month I proposed that the PVRC publish a special scores only edition of this newsletter and discretely asked for volunteers to take on this effort The silence was deafening The PVRC Reunion scores are in the works and I hope to get them out in a special Newsletter that will contain the roster rules and reminiscences of Reunions past If you have any memories you d like to contribute please email them to me As always I encourage you to participate in this effort by contributing your thoughts ideas experience concerns and comments to this publication Please pass along interesting websites and other resources that would be interesting and valuable to our membership I ve listed some in this issue and hope to make this an on going feature See you in Dayton and on the air 73 Eric W3DQ 2 The PVRC Antenna Mount Mike K4GMH Note this was written in response to questions asked on the PVRC reflector A detailed description of the PVRC Mount can be found in the ARRL Antenna Handbook so it won
14. cter grid information That same Saturday May 12 is also the running of the Mid Atlantic QSO Party The MAQP does have a VHF aspect to it allowing contacts on 50 144 222 and 432 which gives you the chance to drum up some VHF action The MAQP runs from 1600z Saturday until 0400z so there is an overlap with the 6 meter Sprint that might provide a few more contacts for your MAQP log All of this of course is just a warmup for the June VHF contest which begins on Saturday afternoon June 9 PVRC is the defending Medium Club category 50 or fewer entries champion While the biggest load is carried by the multiop and some of the high power ops smaller scale entries are just as important for the club s total score as we saw in our recent Sweepstakes win For the last four years the PVRC has been the winner of won the June VHF Contest Club Competition Let s make it five in a row Take some time to fine tune your VHF UHF setup I finally got my small antennas for 6 2 432 and 1296 up on my chimney okay so it took over three years but now it s done See you on the bands Don Dazo K4ZA has finally joined the ranks of the other 17 million assorted bloggers out there in cyberspace He thinks he may be the only one who s writing about ham radio tower amp antenna work The View From The Tower http towerworks journalspace com 3 Where Can You Find PVRC Members The PVRC NW Region de Bud W3L
15. dern octal based equivalents 6K6 6J6 etc and this remained my one and only shortwave receiver for many years Fast forward to the time a few years ago at which point I was living in the United States approaching retirement and had taken up ham radio A colleague and fellow ham introduced me to eBay and the lively trade there in old receivers which in the States have become collectors items I began looking on eBay for a BC 342 HF communications receiver to replace the one I had owned in my teens and now remembered fondly I eventually purchased two along with a U S Army BC 348 Over the next few years I acquired over 30 HF communications receivers through bidding successfully on eBay These were mostly post WWII era vacuum tube receivers manufactured by known British companies e g Eddystone and Racal or American e g Collins Drake Hallicrafters and RME together with a few later model solid state radios built in Japan by the likes of Kenwood and Yaesu Recently I saw advertised Chinese HF military communications receivers that were said to be new i e unused in their original wooden crates After some negotiation with the seller I agreed to buy one of these and had my bank transfer the funds to China The seller warned that owing to US customs rules he would have to repack the radio as it would not be allowed unfettered entry in its wooden crate After some weeks of waiting I had to go to the local post office to sign f
16. f us get together much like the downtown lunch group about every 4 to 6 weeks and visit various restaurants in the Gaithersburg area Downtown Lunch Group de Eric W3D and Brian WV4V Meets on the 3rd Wednesday or Thursday of the month in the downtown area of Washington DC Locations occasionally change but are always Metro accessible Details are sent out on the PVRC reflector Feel free to contact Eric W3DQ w3dq at arrl net or Brian WV4V wv4v at arrl net for details and directions The 2007 W3LPL Annual Open House Saturday June 16th at noon rain or shine The 2007 Fowlfest Saturday August 18th noon 4 Model 339 Chinese Military HF Receiver John N3HBX As a youth one of my uncles helped me build a crystal set which introduced me to the magic of radio From this humble beginning I advanced to building one and two valve battery operated regenerative receivers some of which allowed me to hear amateur radio stations Somewhat later when I began attending the University of Manchester and had joined its Territorial Army unit the sergeant major in charge of the Signals Section sold me a U S Air force BC 342 HF communications receiver which greatly improved my short wave listener capabilities I later traded this for a National HRO model MX receiver with band spread coil set This was an early model HRO employing UX based tubes 6B7 6C6 6D6 etc that I later re valved with somewhat more mo
17. he Winston Salem Courteous Operators Club W4WS meets on the fourth Monday of each month at 7 00 PM in the Pure Chrome establishment 505 Deacon Blvd Winston Salem NC 27105 It s now a biker bar we came with the building so feel free to roar in on your Harley Info at lt w4ws org gt Tidewater de Jose N4BAA Meetings are on the THIRD MONDAY of each month at the QTH of N4BAA for now I have a huge home and can handle just about whomever shows up Over the Hill Bunch de Bill W3AZ The group meets for lunch at noon alternately in Maryland at the College Park Holiday Hotel Route 1 and the Beltway or in Virginia at the Parkview Marriot near Route 50 and the Beltway Meetings generally are held on the last Wednesday of the month and are subject to change Meetings are announced by E Mail All PVRC members non members interested in membership and guests are welcome For information contact Roger Stephens K5VRX rogerergo at netzero net 703 658 3991 for Virginia meetings or Bill Leavitt W3AZ w3az at starpower net for Maryland meetings Central Virginia Contest Club de Ed NW4V Meets the second Tuesday of the month at The Henrico Doctors Hospital Parham Campus located at 7700 E Parham Rd Richmond VA The Hospital is approximately one mile north of the Parham Rd and Broad St intersection The meeting begins at 7PM in the Hospital cafeteria located on the first floor Gaithersburg Area de Jeff K3OQ Several o
18. o boot Their website is http www globalqsl com If you go right now you can get 50 QSL FREE for subscribing Many more features available too GlobalQSL is my QSL management system YCCC 30th Anniversary Mark K1RX 30 President Yankee Clipper Contest Club The Yankee Clipper Contest Club celebrates it s 30th year of competing in the unlimited club category from the Northeastern US Now having close to a membership count of nearly 400 the club has steadily been growing since its inception 1977 the current officers of the YCCC offer the following on the air fun event for both the membership as well as our fellow contesters worldwide For the balance of 2007 commencing immediately YCCC members may sign their calls 30 indicating our 30 year anniversary used as a way to positively promote the YCCC on the air A special certificate will be provided after confirming contacts with at least 10 members This confirmation and request for the special certificate can be done via email at yccc30 gmail com Please indicate the date time frequency call sign of member along with your mailing address so we might send you the certificate QSL cards may be used to confirm these contacts as well and by sending them to Dave W1CTN who will administer the YCCC 30th Anniversary cont Additionally the complete list of YCCC members can be found at www yccc org then click on Members Only and follow
19. ons are appreciated de Glenn K3SWZ k3swz arrl dot net 9 THE R F CONNECTION Specialists in RF Connectors and Coax Tech Support 301 840 5477 24 hour Fax 301 869 3680 Order line 800 783 2666 Email rfc therfc com Please visit us at Http www therfc com Our catalog includes UHF Series N Series BNC Series Adapters F Series DIN Plugs Portable Radio Power DIN Plugs Hardline Connectors Audio Connectors Microphone Connectors FME Series SMA Series Reverse Thread SMA Connectors MCX Series MMCX Series Adapter Kits Reverse Polarity TNC N SMA 39 coax types and 5 balanced lines Tower Works Specializing in Rohn guyed towers Don Daso 515 Withershinn Drive Charlotte NC 28262 704 594 9853 704 408 7948 cell E mail k4za juno com Call or e mail for rates and availability 10
20. or and collect the radio which had been shipped via parcel post This article describes what I found in the package The Chinese military evidently supplied these receivers to their units as a kit that included just about everything that might be needed Besides the radio itself came two pairs of 600 ohm headphones a short wire aerial complete with insulators a maintenance manual and also a test calibration manual both in Chinese of course The radio can be operated off either the mains or batteries The mains power unit which can be switched between 220 and 110 volts is a separate small box that plugs into a compartment at the back of the radio It can be replaced by a battery box two of which were supplied Some ten 1 5 volt D cells are needed to populate the battery box There is also a cable with connectors on either end that allows the radio to be operated from mains or batteries when out of its case for example when being tested on the bench A small balun is included that can be clipped into the antenna terminals for use with balanced antennas Also included are a green canvas case and a pair of shoulder straps that can be clipped onto the radio for carrying it any distance Some of these supplied items can be seen in Figure 1 below The front panel of the radio can be protected by a clip on cover that can be seen in this picture along with the aerial and the two power supply units battery and mains With the excep
21. r but can be switched by a rubber covered switch to the right of bottom center to measure the power supply voltage and check that it is in the proper range A matching rubber covered switch at the left of bottom center turns on the pilot light in the frequency window The small chrome lever nearby will lock the tuning mechanism Two headphone jacks are provided on opposite sides of the front panel There is no built in loudspeaker The small black cap near the center of the front panel can be unscrewed to provide access to a screwdriver adjustment to bring the frequency hairline marker to be correctly positioned when checked via the crystal calibrator The receiver employs two stages of tuned RF amplification followed by a mixer that converts incoming signals down to a first IF of 1 335 MHz The local oscillator frequency is above the receive frequency It is somewhat unusual to have a first IF that is so close to the bottom of the frequency range of the receiver itself Modern practice is to convert the incoming HF signal up in frequency to an IF of around 70 MHz before converting to lower frequencies as this scheme provides good image rejection However the use of direct conversion to 465 KHz as in the above mentioned HRO MX receiver would have resulted in poor image rejection at the higher frequencies The first IF employs a crystal filter at the output of the mixer followed by one stage of gain before a second mixer converts the signals
22. sor of history at the University of Maryland says one problem with the protector was the material it was cut from because plastic promises imperviousness to ruin and to soil but in a way so avowedly artificial that there s another part of us that tends to recoil a bit 8 A New Way to QSL Hal W8HC If you are QSLing via the bureau you may want to consider GlobalQSL It is a new concept in QSLing created by Azar Hami 4X6MI and Paul Gross 4X6UU If any of you have received a 4X WV QSL from the 2006 CQWW Phone contest you know the quality of the printing and the cards themself with 300gr chromo paper Full color both sides With GlobalQSL you design and upload your card Azar will use the PVRC design or choose to create your own then upload your ADIF log that you wish to QSL The QSO info is printed directly onto the card Now comes the good part GlobalQSL will then forward to the QSL bureaus for you They can even forward to the incoming stateside bureaus How much does this cost 82 per 1 000 QSLs Compare the cost of printing full color cards both sides Tired of messing with labels I am With GlobalQSL they print the QSO info directly onto the card Tired of paying a fortune to send QSLs through the outgoing bureaus I am Compare the costs for shipping cards with your bureau If you can find a better deal than GlobalQSL please please please let me know about it Save time and money and have a first class professional QSL t
23. st of you have worked in MANY contests is coming to visit me and PVRC members starting Friday May 11th before going on to the Dayton Hamvention Elvin recently found a new hobby Collecting 48 1 Mini Diecast World War II airplane models You can find examples on this website http www badcataviation com pn1byfrmib html Elvin would like to visit a store that sells these types of models While there are plenty of places to buy these models on line if you know of a store in the Baltimore Washington are please contact me The History of the Pocket Protector posted on the PVRC reflector by Frank W3LPL The New York Times 24 June 1999 There was no such thing as a nerd back in 1947 when Erich Klein opened a small factory on Chicago s North Side and became one of the first manufacturers to make plastic pocket protectors It slipped into a shirt pocket and was useful to anyone who carried a fountain pen or a ballpoint pen which had ink leakage problems said Randy Silton Mr Klein s grandson and president of the company Erell Manufacturing We still make hundreds of thousands a year but most others have dropped them from their lines I guess pocket protectors aren t so popular anymore That s a polite way to put it Made possible by the same heat sealing process used to make World War II flak jackets the pocket protector was intended as an advertising giveaway emblazoned with a company logo But this simple polyvinyl chloride product e
24. tion of the radio which was wrapped in wax paper and in a sealed plastic bag most of the other items were in cardboard boxes that gave off a distinct musty odour as having been stored for many years The case of the mains power supply was somewhat corroded but all else appeared to be in good condition and the seller had done a good job of packing using foam to protect the contents The radio appears to have been manufactured in 1979 based on some entries in the test manual and bears the model number 339 There is no provision for muting the receiver when using it in conjunction with a transmitter so the intended purpose appears to have been for military units needing only a receive capability I was quite struck by the design and workmanship of the radio which seem not to follow western designs of the period The receiver covers the range 1 5 to 30 MHz in six bands 1 5 3 0 3 0 5 5 5 5 9 5 9 5 15 15 22 and 22 30 MHz It is an all solid state design using discrete transistors 26 in all and diodes on printed circuit boards The maintenance manual appears to be very complete with the full circuit diagram and a copy of each of the printed circuits on which the parts placement is indicated The radio is intended continued on the next page 5 Chinese Military HF Receiver cont for reception of AM or CW but the BFO can be offset sufficiently from the IF frequency to allow reception of single sideband On a r
25. volved into something far more culturally symbolic it became the ultimate emblem of nerdiness My first computer course in college was taught by a guy with so many pocket protectors he seemed to be some son of animatronic device with a bad haircut said Alan Robbins an associate professor of design at Kean University in New Jersey Pocket protectors organize tools on the earer s body turning the user into a kind of rudimentary cyborg part human part toolbox In the 1980 s pocket protectors enjoyed a brief hey day Since then they have become self conscious The Massachusetts Institute of Technology Museum gift shop sells a 1 25 protector emblazoned with M I T Nerd Pride a recent Levenger s catalogue offers a leather protector for 19 95 I sometimes poke fun of it as a cultural icon but I feel naked without one said John Shipman an applications specialist at the New Mexico Tech Computer Center in Socorro N M Ever since high school when all the other kids were going down to the gun store to look around I was going to the local office supply store I guess I was a proto geek Edward Tenner the author of When Things Bite Back Technology and the Revenge of Unintended Consequences Knopf 1996 said Now anything as aggressively useful as trying to protect your shirt from ink is anti chic The fact that the pocket protector is a joke Is an example of the triumph of culture over technology Robert Friedel a profes
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