January 2013 Issue - Oxley Region Amateur Radio Club
Contents
1. A representation of the kit available in various models One of the big advantages of Software Defined Radio SDR implementation as described above is that within the limitations of the sound card a spectrum of up to 96 kHz is available on the re ceiver display Those who have used one of the many digital software programs such as Digipan http wb8nut com digital for PSK31 will be fa miliar with the waterfall display of frequency ver sus time The advent of terrestrial Digital Television Broad casting DVB T has created a mass market for USB dongles to enable digital television to be re ceived on home PCs Astute amateurs discovered that some of the cheap popular DVB T USB don gles contained everything required to make an SDR VHF UHF receiver simply by plugging the dongle into a PC and running suitable free soft ware http www vk6th com vk6th SDRdongle htm These provide frequency coverage 65 to 1700 MHz with a gap in coverage between 1100 and 1250 MHz Some readers may already have a suit able DVB T USB dongle for their PCs Not all DVB T USB dongles are suitable A partial list of known suitable dongles may be found at http sdr osmocom org trac wiki rtl sdr The suitable DVB T USB dongles use the Realtek RTL2832U chip which enables the raw I Q quadra ture samples to be transferred to the host computer Dongles which pair the Realtek chip with the Elon ics E4000 chip cover the frequency range of2. Ua Per vaco i First published 1980 Newsletter of the Oxley Region Amateur Radio Club Inc PO Box 712 Port Macquarie 2444 Club e mail address vk2bor orarc org Club Website www orarc org ORARC s Forty second Anniversary Year Club Nets on VK2RPM 146 700MHz CTCSS 91 5Hz Every Sunday at 0830 Every Thursday at 1930 January 2013 ORARC VHF UHF Repeaters Compiled by VK2TT amp VK2AYQ PRESIDENT Henry Lundell VK2ZHE 6582 0534 VICE PRES Bruce Walker VK2HOT 6583 8360 TREASURER Keith Anderson VKFKJA 6586 3988 SECRETARY Henry Lundell VK2ZHE 6582 0534 President 3 Report Welcome to 2013 I trust everyone has had a safe and enjoyable festive season The ORARC 2013 Field Day takes place on Saturday the 8 and Sunday the 9 of June during the Queen s Birthday Weekend The Field Day venue will again be the Tacking Point Surf Life Saving Club building in Matthew Flinders Drive at Lighthouse Beach Last year s Field Day was a great success and this year s event will be even bigger and better Planning for the 2013 Field Day will commence this month so please consider offering your assistance The committee will be very pleased to hear from you The club s communications caravan was on display at the club s Christmas barbeque at the Settlement Point reserve on Saturday the Ist of December 2012 The Christmas celebration was particularly enjoyable with an excellent attendance and perfect weathe
3. coverage isn t quite continuous The good news is that no special drivers are required for Windows and Linux PCs Also these units have built in RF front end filters and a temperature compensated crystal oscillator TXCO for good frequency accuracy With free software such as SDRSharp http sdrsharp com all modes AM FM USB LSB CW etc can be received The user manual indicates that the sensitivity on 2 meters is typically 12dB SINAD NBFM for 0 15uV_ at 145MHz The FUNcube USB dongle was developed to encourage use of the FUNcube satellites as part of an AMSAT UK project However it is possible to explore Software Defined Radio using cheap less than 50 readily available DVB T USB TV dongles and free software http www vk6th com vk6fh SDRdongle htm The down side is reduced frequency coverage 65 to 1700 MHz and a gap in coverage between 1100 and 1250 MHz but there are lots of signals within the accessible frequency range The DVB T USB dongles lack the bandpass filters and some of the other features included in the FUNcube pro USB dongles but they still offer very useable performance Some readers may already have a suitable DVB T USB dongle for their PCs The January 2013 issue of the ARRL journal QST continued page 4 from page 3 contains an excellent article commencing on page 30 entitled Cheap and Easy SDR by Robert Nickels W9RAN which explains how to obtain coverage from HF to 1700 MHz using a DVB
4. Field Day Saturday 12 Sunday 13 January 2013 VK2TT Jan 27 VK2ZHE Jan 24 VK2EM Jan 31 Friday Night Get Together F 201 Friday 18 January 7 00 pm eee VK20A Feb 03 VK2ATM Feb 07 Monthly Meetin Saturday 2 February 2013 2 00 pm VR2CHC Feb 10 VK2ZHE Feb 14 Friday Night Ge t Together VK2TT Feb 17 VK2EM Feb 21 Friday 15 February 7 00 pm VK20A Feb 24 VK2ATM __ Feb 28 Wyong Field Day Wyong Racecourse March 2013 unday 24 February 2013 VK2CHC Mar 03 VK2ZHE Mar 07 Monthly General Meeting VK2TT Mar 10 VK2EM Mar 14 Saturday 2 March 2013 2 00 pm VK20A Mar 17 VK2ATM Mar 21 dy T March 7 00 om VK2CHC Mar 24 VK2ZHE Mar 28 VK2TT Mar 31 John Moyle Memorial Field Day Saturday 16 Sunday 17 March 2013 Bago Car Rally Saturday 23 March 2013 from page 1 issue of Oxtales This time last year APRS was a major topic of discussion amongst club members after an inspirational lecture on the subject by Ashley Anderson VK2XSO at the club s October monthly general meeting in 2011 APRS is short for Automatic Packet Reporting System I am pleased to report that this discussion resulted in a great deal of practical construction which has made our area one of Australia s APRS hotspots with two APRS digipeaters and a great many members fitting and using trackers in their vehicles Ross VK2RR Arthur VK2ATM and John VK2FGAA at the VK2RPM Voice and APRS Repeaters The club s two 145 175 MHz APRS digipeaters are VK
5. HISTORIC PRECINCT Ug TELEGRAPH STATION ae TRY SSE MAHA Tg 1 ey Ei Message as received by Henry Beechworth Telegraph Station a brief overview reprinted from the information brochure of the Historic and Cultural Precinct Ihe Electric Telegraph Wire snaked its way across country to Beechworth in late 1857 By 1858 this modern wonder of communication was housed in the Telegraph Station next to the Court House Early illustrations show it as a single sto rey building set back from the street in line with its neighbours The double fronted facade had a central entrance featuring a two storey tower us ing a Sliding ball to indicate the time Beechworth marvelled at the onset of instant com munications between itself Melbourne and Syd ney and eventually the rest of Australia and the world The telegraph proved a great boon for business and government officials and of course it was highly valued for personal messages The postal and telegraph departments were com bined in 1869 and the telegraph function was probably transferred to the post office around that time The Telegraph Station Manager was pro moted to Postmaster in December 1870 In 1871 11 the building was again remodelled with the addi tion of a large office fronting Ford Street and the remaining rooms to the rear became the residen tial accommodation for the District Surveyor The building was last used as the Beechworth Of fice of the Department o
6. T USB dongle and a simple up converter for HF and 6 meters Of course there is a wealth of information on the subject available on the internet Closer to home ORARC club member Bruce Ekert VK2EM has used modified Ku and C band LNBs in conjunction with a DVB T USB dongle to build a microwave spectrum analyser as an aid to tuning up his microwave transverters There are many commercially available sophisticated software defined receivers and transceivers such as the FlexRadio http www flex radio com Many amateur transceivers already use the digital signal processing DSP techniques that are employed in pure SDR equipment Hopefully this has whetted everyone s appetite appetites Please see the short article with several useful internet links to useful information which I have compiled for this issue of Oxtales We look forward to arranging some talks and practical demonstrations of SDR at club meetings in the coming months The club s 2013 calendar is the most popular yet with photos of 68 of our members Preparation of this year s calendar represents a lot of detailed work on the part of John Hansen VK2AYQ The annual calendar has become highly sought after for its member picture gallery and club information Copies are still available and may be purchased at the January Friday night get together on the 18 of January and at the Monthly General meeting on Saturday the 2 of February 2013 and at subsequent meeting
7. kHz is an outcome of the ITU World Radio Confer ence in 2012 WRC 12 The ACMA has amended the conditions in the LCD that gives effect to the WRC outcomes authorising a radiated power of not more than 5 watts pX EIRP with a maximum emission bandwidth of 2 1 kHz There is however two exclusion zones where amateur operation is not permitted so as to protect aeronautical non directional beacons NDB operating in the Ex mouth and Timor regions Also included in the amendments is the withdrawal for general use by advanced licensees to the ama teur secondary allocation 420 to 430 MHz to allow for greater harmonisation of government services in the 400 MHz band following the ACMA s re view of this band The use of this segment by ama teurs was mainly for fixed links associated with repeater interlinking and a number of ATV chan nels where alternative channel assignment have been achieved in the 430 to 450 MHz 70cm band The Beechworth Telegraph Station By John VK2AYQ Whilst travelling through Victoria in June 2012 I came across the Beechworth Telegraph Station The building is made up of beautifully restored sandstone situated in the Beechworth Historic and Cultural Precinct I was excited to find that inside there is a functional replica of the actual Telegraph station complete 10 with Morsecodians who for a small fee will send Telegrams The telegrams are sent via a bug or straight key which is connected
8. 2RPM 1 at the VK2RPM repeater site at Middle Brother Mountain and VK2RCN 1 at the VK2RCN repeater site at Telegraph Point Thank you to everyone who contributed to building testing and installing these two digipeaters last year They have proven to be a very important part of the overall national APRS infrastructure They each digipeat some thousands of position packets from both local and transiting APRS trackers each month VK2RPM voice and APRS Repeaters Special thanks must go to and Arthur Monck VK2ATM and John VK2KC who sourced the hardware for the APRS trackers Club members set up about 25 trackers during the year If you have a tracker and haven t used it for a while why not plug it in and add to the many APRS tracks which appear daily in the Port Macquarie Wauchope Taree and Kempsey areas on APRS Google Maps http aprs fi To learn more about APRS visit the APRS Australian web site http www aprs net au This year the club will continue to foster hands on radio activities One of these activities is to encourage experimentation in Software Defined Radio SDR techniques which is an excellent marriage of radio and computers Many readers may have read about the FUNcube Pro USB SDR dongle http www funcubedongle com page_id 1073 which covers 150 kHz to 1900 MHz These come from the UK and cost about AUD 230 including international postage to Australia These have a gap in coverage from 240 to 420 MHz so the
9. 64 to 1700 MHz with a gap from 1100 to 1250 MHz Since dongles which use the Realtek chip perform the task of extracting the I Q digital data within the dongle and do so much faster than is possible with an external sound card an SDR receiver using one of these dongles can display a spectrum of up to 2 MHz wide The January 2013 issue of the ARRL journal QST http www arrl org files file QST ThisMonthinQST January2013 TOC pdf contains an excellent article commencing on page 30 enti tled Cheap and Easy SDR by Robert Nickels W9RAN which explains how to obtain coverage from HF to 1700 MHz using a DVB T USB dongle and a simple up converter for HF and 6 metres Of course there is a wealth of information on the sub ject available on the internet As I mentioned in my President s Report ORARC club member Bruce Ekert VK2EM has used modi fied Ku and C band LNBs in conjunction with a DVB T USB dongle to build a microwave spec trum analyser as an aid to tuning up his microwave transverters http www vklogger com forum viewtopic php f 23 amp t 10527 p24765 Many readers may have read about the FUNcube Pro USB SDR dongle http www ftuncubedongle com page_id 1073 which covers 150 kHz to 1700 MHz These come from the UK and cost about AUD 230 including interna tional postage to Australia These have a gap in Continued page 9 Continued from page 8 coverage from 240 to 420 MHz so the coverage isn t quite cont
10. RGxjVEIDNDJgqaW8 edit phi 1 W9RAN SDR Sharp User www goo gl suS2w VK2EM SDR posting _ http www vklogger com forum viewtopic php f 23 amp t 10527 p24765 FUNcube web site http www funcubedongle com SDR Radio FUNcube support _ http www sdr radio com Software FUNcubeDongle tabid 475 language en GB Deftault aspx SoftRock WB5RVZ Software Homepage http wb5rvz com sdr SoftRock principle explained http softrocksdr wikispaces com How Softrocks Work Ensemble RXTX Project http www wb5rvz com sdr ensemble Current Ensemble TXRX_ Project information http www wb5Srvz org ensemble_rxtx index projectId 14 SoftRock Kit Supplier http fivedash com SoftRock Ensemble SDR Tx Rx kit fivedash com index php main_page product_info amp cPath 1 amp products_id 7 amp zenid Ibc190Sac9b8 amp cad7el 2d4f4d1cSedb27 WB8NUT Digital Modes Information Page http wb8nut com digital FlexRadio http www flex radio com Guide http Defined Radio http Henry VK2ZHE oe i h TESTBED 2012 2012 a New 630 meter band Date 01 01 2013 Author Peter Young VK3MV From WIA Website ACMA Makes Amendments to the Amateur Li cence Conditions Determination LCD The new 630 meter band is now a reality Effective from the Ist January 2013 Australian Advanced amateur licensees can now operate in the new band 630 meters on a secondary basis This new world wide allocation from 472 kHz to 479
11. andwidth and to de modulate received signals and to modulate RF for transmission these tasks are carried out by digital signal processing DSP techniques The interface which gives the user control over these functions can be an interactive computer touch screen or a conventional computer display with a keyboard and mouse for input or a conventional radio front panel with a display and buttons and knobs for control all under control of an embedded computer There are many commercially available sophisti cated software defined receivers and transceivers such as the FlexRadio _ http www flex radio com Click Here THE GAME HAS CHANGED a Many current model amateur transceivers already use the same digital signal processing DSP tech niques that are employed in pure SDR equipment There have many articles published over the last decade describing methods for affordably experi menting with software defined radio It is possible to build a homebrew RF interface to connect to a sound card to enable a home computer to be used with free software to receive radio signals Simi larly there are various kits and ready built inter faces available Many Amateurs will be aware of direct conversion receivers which use an oscillator on or close to the same frequency as an incoming signal to mix with the incoming signal to directly produce a hetero dyne at audio frequencies A simple audio band pass filter feeds these pr
12. f Natural Resources and Environment until 1999 renovated and re opened as part of the Historic Precinct in October 2001 I would thoroughly recommend a visit to the Tele graph Office and indeed Beechworth with its col lection of Historic Buildings The Morse Sounder sidewinder mechanical bug and straight key used to send Telegraphic messages From the Bee chworth Telegraph Office display Who thinks that SMS and text messaging is a new concept I came across the above in the historical display of a comment written in January 1901 The ideas were there even if it took many years for the technology to be developed
13. ical 7 148 Lake Rd Port Macquarie Ph 02 6581 4476 Jaycar 1s a major sponsor of our calen dar Only 2 from Henry VK2ZHE Christmas Meeting The Club s Christmas Meeting on Saturday 1 December at Settlement Point Park once again was a very enjoyable event The weather smiled on us with a fine day and a cooling breeze to keep the heat at bay The site is secured Larry VK2CLL Lewis VK2AG Richard VK2CHC and AlexVK2FOAB are ready for anything F Hi kRE amp g aN The cooks clean up Keith VK2FKJA Bill Wy gee A VK2ZCW and Richard VK2CHC XYL s keeping the group in line Arthur VK2ATM and Neil VK2EI share a thought Dave VK2AYD enjoys the traditional ice cream and fruit salad Paul VK2UPR striding along to the meeting A fine body of men Charles VK2KCE John VK2AYQ and Mark VK2FMGM Tim VK2ZTM takes some time out Coralie Bill VK2ZCV Dennis and Heather share a laugh p i EA i oP a W x F rel a lih ss Si David VK2FRAB looks for provisions Software Defined Radio SDR By Henry VK2ZHE Software Defined Radio SDR is the direction that radio receiving and transmitting technology is headed Implementation of SDR radio still requires RF circuitry to receive incoming radio signals and to amplify generated radio frequency energy to a power level suitable for transmission However instead of using conventional RF filters to define received and transmitted RF b
14. inuous The good news is that no special drivers are required for Windows and Linux PCs Also these units have built in RF front end filters and a temperature compensated crystal oscillator TXCO for good frequency accuracy With free software such as SDRSharp_http sdrsharp com all modes AM FM USB LSB CW etc can be received TA i et an y D W Me My Canin MEK soma a The user manual indicates that the sensitivity on 2 metres is typically 12dB SINAD NBFM for O 15uV at 145MHz The FUNcube USB dongle was developed to encourage use of the FUNcube satellites as part of an AMSAT UK project This article barely scratches the surface of SDR It is hoped to run a series of talks and demonstrations on the subject at ORARC club meetings during 2013 Offers to share your knowledge and experi ence with fellow members will be greatly appreci ated Please contact the Committee at any time Henry Lundell VK2ZHE Below are links to some sites which will be of in terest VK6FH SDR page http www vk6th com vk6th SDRdongle htm Partial list of compatible DBV T Devices http sdr osmocom org trac wiki rtl sdr SDR Sharp website http www sdrsharp com SDR Sharp Download Page http www sdrsharp com index php downloads RTL2832 DVB T Dongle Installation http rtlsdr org softwarewindows SDR Sharp Yahoo Group http uk groups yahoo com group SDRSharp W9ORAN SDR Info https docs google com folder d OB98akUIPlomI
15. oducts to the audio ampli fier which requires considerable gain in order to make the receiver sensitive enough for practical use This technique avoids the need for converting the incoming signal to an Intermediate Frequency IF as is done in a conventional superheterodyne receiver While there are disadvantages in this method it is often used in simple receivers for QRP and experimental use Of course the detector output of a direct conversion receiver contains more than just audio frequencies All frequencies passed by the RF circuitry ahead of the mixer will beat with the local oscillator to pro duce sum and difference products extending up to many Megahertz if the front end filter is wide enough In fact in a conventional superheterodyne receiver the IF amplifier simply passes a small band of frequencies in this spectrum and amplifies and filters this energy before demodulating it in typically a simple diode envelope detector for AM signals or a mixing the energy with a beat frequen cy oscillator BFO in a product detector to detect AM or SSB signals In this example the secret to hearing a desired signal is that the difference in fre quency between the desired signal and the oscilla tor used to mix with the incoming RF must be equal to the intermediate frequency One type of Software Defined Radio SDR receiv er makes use of the relatively wide band of fre quencies available at the output of a direct conver sion receiver The
16. output of the receiver is first dig itally sampled by an analogue to digital A to D converter The bandwidth 1 e the range of frequen cies sampled is dependent upon the speed of the clock used to make the samples and upon the num ber of digital bits in each sample 1 e the resolution of each sample This sampling is done in quadra ture giving two data streams known as the I and Q streams which are able to be digitally manipulated under software control to select and detect a de sired signal One common method for experiment ers to achieve this is to feed the I and Q outputs of a direct conversion receiver into a computer stereo sound card To obtain the quadrature I and Q streams the direct conversion receiver uses a local oscillator with two outputs 90 degrees apart Soft ware freely available for download from the inter net is then used to perform all the Software De fined Radio SDR receiver digital signal pro cessing DSP functions necessary to receive in coming digital and analogue signals transmitted in virtually any mode A popular example of this technique is the SoftRock series of kits As a bonus Continued page 8 from page7 the SoftRock kits include a complete 1 Watt HF transceiver kit the Ensemble RXTX Project http www wbdrvz com sdr ensemble for which cur rent information may be found at www wb5rvz org ensemble_rxtx index projectId 14 and kit pricing at http fivedash com for les than US 100 http
17. r Thank you to everyone who participated in the festivities and a special thank you to the many people who assisted with the running of the day Thank you to everyone who took photos and provided them to the editor for inclusion in this Continued on page 3 MIDDLE BROTHER VK2RPM 2 metre Voice CTCSS 91 5Hz O P 146 700MHz I P 146 100MHz VK2RPM 70 cm Voice CTCSS 123Hz O P 438 525MHz I P 433 525MHz VK2RPM 1 APRS Digipeater SX 145 175MHz 1200bps TELEGRAPH POINT VK2RCN 2 metre Voice O P 147 000 MHz I P 146 400 MHz VK2RCN 70 cm Voice CTCSS 123 Hz O P 438 425MHz I P 433 425MHz VK2RCN 1 APRS Digipeater SX 145 175MHz 1200bps In This Issue Page No Front Cover Item President s Monthly Report Down the Coax E Mail Directory Net Controllers Roster Calling Frequencies Christmas 2012 meeting Software Defined Radio New 630 meter band Don t forget to join or renew your WIA i membership BQ y ill oe INSTITUTE amp http www wia org au Net Controllers Roster Down The Coax l Nets on Voice Repeater VK2RPM 146 700 MHz Ross Hill Memorial Contest 1 to 31 January 2013 a Sundays Thursdays Monthly meetings held in the S E S Building 0830 Local 1930 Local Central Road Port Macquarie January 2013 Monthly Meeting VK2TT Jan 06 VK2ZHE Jan 03 Saturday 5 January 2013 2 00 pm VK20A Jan 13 VK2EM Jan 10 VK2CHC Jan 20 VK2ATM Jan 17 Summer VHF UHF
18. s The Mid North Coast Amateur Radio Group MNCARG has advised that there will not be a Radio Expo in Coffs Harbour in January 2013 The Central Coast Field Day at Wyong Racecourse is on Sunday the 24 of February 2013 The gates and the Flea Market open at 6 30am and the traders open at 9 00am For more information see http www fieldday org au Best wishes for a happy and healthy 2013 Henry Lundell VK2ZHE President CALLING FREQUENCIES Submitted by John VK2KC John has recently returned from a 2 month trip during which John had contact with other Radio Amateurs whilst on the road John has compiled the following list of calling frequencies that club members may find useful either on trips or at home Please note that these frequencies are used for providing clear channels for calling and one should QSY off the calling frequency once communications are established Australian voice calling frequencies 3 650 7 090 14 190 21 190 28 590 52 160 World CW calling frequencies 3 570 7 030 14 060 18 080 21 140 24 910 28 180 50 160 World voice calling frequencies 3 690 amp 3 940 MHz 7 090 amp 7 190 14 290 18 140 21 360 24 960 28 390 50 160 Calling frequencies for Slow Scan TV SSTV 3 630 7 033 14 227 Calling Frequencies for PSK31 14 070 Members may care to add these frequencies to the diary s log books smart phones and tablets for future use Better More Techn
19. to a telephone line via a modem A Morse operator establishes a contact with a receiving station and the telegram is sent The sending and receiving stations are staffed by volunteers and are dotted around Australia The receiving operator types the re ceived message onto a facsimile of an old tele graph form and the message is delivered to the ee by pon Telegram that is filled out and presented to the operator The operator at Beechworth was Leo Nettle who had been a Post Office telegraph operator and really swung the old mechanical bug and straight keys Although Leo was only sending at around 25 words per minute I couldn t read the Morse on the sounder receiver as the operator reads the spaces between the sound clicks He said that he was able to read both what he called radio Morse and Post Office Morse without any trouble however some people apparently never get the hang of Post Office Morse Leo sending a telegram using the straight key continued page 11 from page 10 There was even a local connections with our club Trevor VK2TT was one of the people who had designed and set up the network and modems People were fascinated watching Leo sending and receiving messages and it was a really great way to understand one aspect of our communication history I sent Henry VK2ZHE a telegram asking him to give my apologies to the next meeting This telegram was sent by Morse code from BEECHWORTH
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