Mills Weekend, Vintage Radio Station, Band Reports, A different antenna mount & more...
Worthing & District Amateur Radio Club Established 1948
http://www.wadarc.org.uk - email firstname.lastname@example.org President: G8FMJ John Slater
Life Vice President: G8MSQ Peter Robinson
WADARC meets alternate Wednesdays, 8pm in the Lancing Parish Hall, South Street, Lancing BN15 8AJ. All who have an interest in radio communications and associated subjects, whether a licensed amateur or not, are invited. WADARC can also arrange training for people to undertake the Radio Amateur Foundation, Intermediate & Advanced licenses. WADARC Committee 2011 - 2012 Kelvan! ! Rod! ! Sandra ! ! John ! ! Richard! ! Jonathan! Peter! ! Pete! ! Andy! !
M0KEL! ! M0RDV! ! G0KAG! ! G8FMJ! ! G7NLZ! ! G1EXG! ! G4LKW! ! M6PAP! ! M6RFE! !
Chairman! ! Secretary! ! Treasurer! ! President! ! Ordinary Member!! Ordinary Member!! Ordinary Member!! Ordinary Member!! Ordinary Member!!
WADARC Ex Officio 2011 - 2012 John ! Peter! Chris ! Graham Phil! Martin !
! ! ! ! ! !
G8FMJ! ! G8MSQ! ! G3NDJ! ! G4FNL! ! G4UDU! ! M0ADY ! !
Publicity!! ! Membership Manager! Awards Manager! ! Contest Manager!! Ragchew Editor! ! Club Webmaster! !
WADARC Foundation, Intermediate & Advanced Courses & Licensing Kelvan! !
Training Officer! !
WADARC Club Nets - all times are local I am currently obtaining new information on club nets. 2m on 145.425 is an often used frequency
Contents From the Editor's Keyboard!
A Different Antenna Mount!
Listening to the International Space Station!
Construction of a Vintage Radio Station - Part 2!
Club Member Profile G3NDJ!
St Dunstanâ€™s Ralley!
In Conclusion - Electronic Ragchew!
Club program, activities and dates for the diary!
From the Editor's Keyboard This issue is being put together in Austria - time ran very short this month and all of the requirements we had for radios for the Jubilee weekend resulted in very little time being available for anything other than WORK! On Monday morning 11th June we departed in heavy rain and as soon as we reached Small Dole we encountered our first flood, water running across the road for about 100m, flowing very fast and about 40cms deep in the middle. Floods on the roads all the way to Dover for the 07:30 ferry, then heavy rain all the way on the drive down through Belgium to Luxembourg for our first stop. This was chosen as a good place for the first night - good campsites and CHEAP diesel at 98p per litre! Next morning on the road again, nearly 500 miles to go, driving through the centre of Germany and down to the border crossing at Kufstein, with the very important stop to purchase a “Vignette” - the permit to use the Austrian Motorways. This is 8 Euros for 10 days. Then it was into the mountains in the Tyrol area of Austria. We plan to be here for a few days then head west towards Lake Constance in southern Germany and the radio show at Friedrichshafen on the 22nd - 24th June. Taking lots of pictures - should have some to show on a club night in July, plus getting on the radio whenever I can. I operated from LX Luxembourg, so that’s a new one for my “radio from” countries and with a bit of luck I hope to be on from HB0 Lichtenstein. I know from the WX reports I am hearing on the bands the conditions are not too good in the UK - so must soldier on and get this finished, a lot cooler today, only 30C. Phil G4UDU
Chairman’s Chatter It was very sad news to hear of the death of Denzil, he will be missed at the club; he would always help out with any problems for new licensed members. Our condolences go out to his family. Big thanks to John for organising the program. I am starting a foundation course on Wednesday 20th June at the Parish Hall, 6.00 start. The meetings being held weekly again seems to be popular.
Don’t forget the Fire Station Open Day on July 28th. Hope to see you all at club meetings and on the air. 73, Kelvan Gale M0KEL
Presidential Ponderings Time for another Ragchew, don’t know where the time goes, it just seems to fly by, everyone keeps telling me it just seems like that as you get older but I”m not convinced. Since the last Ragchew, you, the members decided to go back to the old weekly format for club meetings, a decision, I have to say I was a little sceptical about at the time and doubted that we would get the level of support to keep this going, and I will hold my hands up and admit I was wrong. Not only have the meetings been well attended, we have also GAINED some new members, quite an achievement these days. I have to say that the new layout of the chairs has had a great effect on the interaction of members at these meetings, with everyone feeling they can join in, a really positive thing. As I have commented on in my regular weekly waffle, I have had to give up banging my head against the proverbial brick wall and I've undertaken the task of getting a club programme in order. This is now sorted for the next few months and will be updated for the rest of the year. I have got some talks lined up and hope we can get a good turnout for these. I will keep this going for the time being BUT I would still like someone to take this up in the future, please give it some thought. We are now rapidly heading for the summer and the various special event stations we are going to be activating. We have already done the Mills weekend with some success and hope that we can again count on your support for other such events, we will keep posting regular updates on the email reflector. This brings me again to the thanks we all owe to Martin M0ADY who despite having had many personal problems has kept our email and website system up and running, thanks again Martin. It is with regret that after such a positive time for the club we have the occasional low, and this time it has to be the loss of a good friend and great supporter of the club, Denzil G3KXF. We all have our own memories of Denzil and he will be
missed by us all. At the time of writing this, further arrangements have not been forthcoming but as they do I hope we can give him the send off he deserved. I must apologise on behalf of the club for the problems regarding training courses. I know we have a number of new members wishing to get on the licence ladder and it's nice to see that Kelvan will be starting courses again soon. My personal nightmare (the Digital Switchover) has now been and gone, for the most part, although we are still sorting out odd issues caused by these events. However, it does mean that I am not working 24/7 and have had much more time to get on the radio, and I have to say with some success in working not only DXpeditions but a few new countries as well, very enjoyable. Keep up the good work people, see you soon.
73, John G8FMJ
A Different Antenna Mount While I am away, I like to get on the radio whenever possible, usually on the HF bands, but quickly setting up antennas is often a problem. I always have an HF mobile antenna with me and when space is at a premium (you need to see a German camping site to understand this - if there is empty space it is wasted money and some site owners pack everyone in and ignore the
regulations!) and this is often a quick and easy way to get on the air. So, although I have a 13m telescopic vertical mast from which I can use as a radiator or hang wires from, a more simple approach is often required. I am lucky with this vehicle because although the previous one we had utilised an all fibreglass body, the current German vehicle has an aluminium outer shell. Now this does present a minor problem in that mag mounts tend to be rather ineffective so a “Plan B” was called for.
I wanted something that would give a reliable mounting without drilling holes so after an “idea moment”, I thought about those handles you can get for carrying sheets of glass, the ones with the rubber suction cups and the levers to lock out the air and get a very secure grip - so off to B & Q and yes there they were - at £8.99 this must be worth a try. The first picture shows the double suction cup device with a standard mobile mount attached to the handle section. There is also a short section of copper braid added with a “Croc Clip” to attach to a grounding screw for a perfect earth. The second picture shows the antenna mount on the top of the roof with the tabs locked down and the Outbacker mobile whip on the top.
Next get an antenna mount that is designed to clamp around an object, apply to the handle, add some feeder cable and the mount is made. I have been using this for a couple of months now - it works very well and is easy to make too. I recommend you give it a try if this type of antenna fixing is useful for you. Phil G4UDU
Listening to the International Space Station
The International Space Station - top side view! On May 14 three more radio amateurs flew to the International Space Station (ISS) bringing the total number of hams on-board to six. The three newcomers are NASA Flight Engineer Joseph Acaba KE5DAR and his two Russian crewmates, Soyuz Commander Gennady Padalka RN3DT and Flight Engineer Sergei Revin RN3BS. They have joined Expedition 31 Commander Oleg Kononenko RN3DX of the Russian Federal Space Agency,
Flight Engineer Don Pettit KD5MDT of NASA and Flight Engineer Andrei Kuipers PI9ISS. History The first amateur radio equipment was delivered to the International Space Station (ISS) in September 2000 and an amateur radio station was established on-board for use by astronauts who are licensed radio amateurs. Commander William Shepherd KD5GS made the first amateur contacts in November of that year. Most of the astronauts on the International Space Station are licenced radio amateurs and sometimes during their spare time they talk to other radio amateurs back on earth. There is a special thrill in talking to an astronaut out in space! What equipment do you need to hear the ISS? The amateur radio station on the ISS can be received using very simple equipment. Almost any 144 MHz FM rig will receive the ISS, you can even use a general coverage VHF scanner with an external antenna. As far as the antenna is concerned, the simpler the better. My favourite is a ¼ wave ground plane as it has a high angle of radiation. I’ve found large 2m colinears don’t work quite as well since the radiation pattern is concentrated at the horizon. You can receive the ISS outdoors using a 2 metre hand-held with its helical antenna but a 1/4 wave whip will give far better results. In the UK we use narrow 2.5 kHz deviation FM but the ISS transmits using the wider 5 kHz deviation used in much of the world. Most rigs can be switched been wide and narrow deviation filters so select the wider deviation. Hand-held rigs all seem to have a single wide filter fitted as standard. What will you hear? Much of the time the Space Station equipment operates in “automatic mode”. It can act as an AX.25 packet repeater, voice repeater or transmit Slow Scan Television (SSTV) pictures. Voice and SSTV transmissions take place on 145.800 MHz FM, when they are not active AX.25 packet may be heard on 145.825 MHz. The aim to start with is simply to listen to the sounds from the satellite. You can check the current mode of operation on the ISS Fan Club website. The ISS amateur radio station is used for school contacts. These educational contacts enable students to communicate directly via amateur radio with the astronauts and ask them questions. In recent years a number of UK schools have
made contact with the space station thanks to GB4FUN and volunteers from AMSAT-UK. When the astronauts put out a CQ call they also use 145.800 MHz FM but operate “split” listening for replies 600 kHz lower on 145.200 MHz. If you are lucky and hear them calling CQ just remember to activate your rigs repeater shift to ensure you reply on the correct frequency. You should never transmit on 145.800 MHz. When to listen The ISS is in a very low orbit and so is only in range 5 or 6 times each day and then only for a maximum of 10 minutes on the best orbit. This means you need to make sure you’re listening at the right time to hear it. There are a number of websites that tell you when to listen. I use the orbital predictions on the ISS Fan Club site. Doppler Shift The International Space Station is traveling around the Earth at over 28,000km/h. This high speed makes radio signals appear to shift in frequency, a phenomenon called Doppler Shift. This Doppler Shift will cause the ISS transmit frequency of 145.800 MHz to look as if it is 3.5 kHz higher in frequency, 145.8035 when the ISS is approaching your location. During the 10 minute pass the frequency will move lower, shifting a total of 7 kHz down to 145.7965 as the ISS goes out of range. To get maximum signal you ideally need a radio that tunes in 1 kHz or smaller steps to follow the shift but in practice acceptable results are obtained with the radio left on 145.800 MHz. AMSAT-UK The Amateur Satellite organisation in this country is AMSAT-UK. Its members are involved in the construction of new amateur radio satellites and in running the stations used for ISS school contacts. The group produce a quarterly A4 colour publication OSCAR News that is full of information on the Amateur satellites. You can join online via the AMSAT-UK website http://www.uk.amsat.org/ Get the latest status of the space station at the ISS Fan Club http:// www.issfanclub.com/ Orbital Predictions (select ISS) http://www.amsat.org/amsat-new/tools/predict/ The IZ8BLY Vox Recoder enables you to record the ISS on 145.800 MHz FM while you’re away from home http://antoninoporcino.xoom.it/VoxRecorder/ Amateur Radio on the International Space Station (ARISS) http://www.rac.ca/ ariss/oindex.htm
The above picture shows: The six radio hams comprising the ISS Expedition 31 crew. In the front row are Russian cosmonauts Oleg Kononenko RN3DX (right), commander; and Gennady Padalka RN3DT, flight engineer. Pictured from the left (back row) are NASA astronaut Joe Acaba KE5DAR, Russian cosmonaut Sergei Revin RN3BS, European Space Agency astronaut Andre Kuipers PI9ISS and NASA astronaut Don Pettit KD5MDT, all flight engineers. Photo credit: NASA
Mills Weekend A nice sunny weekend in May had WADARC participating in Mills on the air. The team arrived to set up on the Sunday morning, very soon there was the mast with the club trap dipole in inverted “V” configuration and the 2m antenna was placed by Peter in the top of the mill. Equipment was set up and by 10:30 there was an HF and a VHF station on the air. Totals for the weekend were as follows:Total QSO’s! 89 Mills on HF! 18 Mills on VHF!1 Best “DX Mills” were two in Holland.
Arriving on site at 09:00
Pete G4LKW at the HF Station
Pete G6PAP at the VHF Station
New GB0HSM QSL card
Many thanks to all who took part operating and helped set up equipment for this event.
Construction of a Vintage Radio station - Part 2 In the last Ragchew I mentioned a project where a vintage radio station comprising 1939 era was constructed to provide a demonstration working station on the 7, 10 and 14MHz amateur radio frequency bands using CW. The receiver section of the project, a National HRO receiver in a restored original condition, was described. This part describes the transmitter section of the project, which is shown in Fig 1. The Original Transmitter Trying to find a suitable transmitter proved to be difficult but I eventually came across a transmitter type UHX-25, made by Harvey Radio Laboratories, INC, Cambridge Mass, USA. I have a Harvey catalogue that includes this transmitter and is dated 1939.
The UX-25 is quoted as covering 5 to 200 meters (1.5 to 60MHz). This was achieved using a crystal controlled oscillator followed by a multiplier whose frequency range was set using plug-in coils. I am not sure of the power amplifier/antenna coupling arrangement. The brochure says â€œA special five point switch accessible through the hinged cover permits either series or parallel tuning of the antenna feeders and also selects various fixed capacitors in the parallel position for proper loading of the antennas throughout the frequency range of the transmitter without the need for external condenser or coil combinationsâ€?. I guess it is a sort of internal antenna tuning unit but I didnâ€™t have enough of the original components or a schematic to check this out. The transmitter line up comprised a 6L6 oscillator followed by a 6L6 multiplier. The PA used an 807 running 50watts input [see note 1]. The transmitter used a pair of 6L6s for high-level amplitude modulation.
Rear view of my Harvey transmitter UHX-25 before rebuilding. Most of the components in the foreground were used in the original amplitude modulation section. The Yaxley switch in the top right is an undefined modification, possibly to switch in an optional external VFO
My UHX-25 was unusable in its original state. It had been stored in a loft for over 60 years and most of the passive components were poor condition. Even simple toggle switches didn’t work, probably due to corroded contacts. The original crystal holder had been removed and replaced with a yaxley switch and an additional screened coax type socket – I think it was a modification for an optional external VFO connection. The ceramic valve holders, variable capacitors and meters were pressed into service; all they just needed was just a bit of a clean up. For my demonstration vintage station the amplitude modulation section was not required. The modulation stages and transformer took up half of the original transmitter chassis space as can be seen in Fig 2. When these components were removed there was enough space for a power supply. An internal variable frequency oscillator (VFO) was also required. The RF power amplifier circuit was rebuilt using a single ended Pi output arrangement to meet modern emission criteria. Considering all the changes required I decided to make a new chassis rather than modify the old one. The original front panel with the original control labels was used and wherever possible the labelled controls provided same functions as in the original transmitter. Transmitter Construction considerations The construction of this transmitter was partially determined by the contents of my junk box. I also had what originally was a partially built home brew HF linear, which had been doing duty as a 500kHz transmitter for the last couple of years but was no longer required. The most valuable component on this chassis was the mains transformer described on its label as a ‘RadioSpares deluxe transformer’. Its voltage output windings comprised 450-0-450, 350-0-350 and a couple of fairly high current 6.3s and a 5v. A further consideration was the type of power amplifier valve to use. The original UHX-25 used a single 807, which requires 750v on the anode to obtain full RF output. Because my transformer could only manage 500Vdc I decided to use two 807s in parallel to get the most power from the available supply. The original UHX-25 was crystal controlled. This frequency control method would restrict its use as a demonstration station and a VFO was required. As mentioned earlier, I wanted the transmitter to cover the 7, 10 and 14MHz amateur radio frequency bands using CW. This was achieved using a VFO with a frequency range of 3.2 to 3.6MHz. On 7MHz this would require frequency doubling from 3.5MHz and quadrepelling from the same VFO frequency on 14MHz. The 10.1MHz band was covered by tripling up from 3.366MHz.
The source of most of the information for building a transmitter of this type came from the ARRLâ€™s The Radio Amateurs Handbook, 1947 edition. Although this represented a later period than the UHX-25 the technology for HF transmitter design had changed very little since 1939. Many of the transmitters described in this handbook still used crystal control, 6V6, 6L6 and 807 valves and link coupling from the PA to the antenna. My VFO was built as described in this ARRL book and uses a 6SK7 valve in an electron coupled high-C Hartley oscillator circuit. This VFO was built in a die-cast box as a separate entity. This enabled it to be tested for frequency range and stability before being built into the transmitter. The main problem was finding a suitable slow-motion dial. A 3inch diameter control/dial was the maximum that could be accommodated on the front panel without encroaching on to other controls and spoiling the symmetry of the layout. The dial shown in the picture below was used in early RAF radio equipment so while the vintage is right the pedigree is not. I am looking for a suitable dial that originates in the USA.
The front panel of the rebuilt UHX-25 Harvey Radio The next consideration was the frequency multiplier/driver stages. Traditionally the 6V6, or its bigger brother the 6L6, was used for this purpose. I had considered using the more efficient 6AG7 but these valves were not available in 1939 so I
reverted to 6V6s for both VFO isolator/amplifier and multiplier. The tuned capacitors in these circuits were mounted behind the controls labelled OSC PLATE and DOUB PLATE as in the original transmitter. Plug-in coils were used in the original to enable the transmitter to cover the frequency range mentioned earlier. In this case the transmitter was only required to cover the 7, 10 and 14MHz bands and some experimenting showed that this could be done without changing coils. The multiplier stage doubles the 3.5MHz VFO output to 7MHz and this is used to drive the PA stage on 7MHz and 14MHz. On 14MHz the PA stage operates as a doubler. On 10.1MHz the multiplier stage triples the 3.666MHz VFO output to 10.1MHz to drive the PA. The general design of the transmitter is shown in the following block diagram,
Block diagram of the modified Harvey transmitter The original antenna link coupling arrangement was replaced with a Pi output circuit for greater harmonic suppression, availability of components and ease of
operation. As mentioned earlier I wanted to use the original labelled controls to do what they said they did. The anode tuning control labelled AMP PLATE was originally fitted under the chassis. The new anode tuning capacitor was too large to be fitted this way and the problem was overcome by fitting it to the top rear of the chassis where it is operated via a mechanical link from the AMP PLATE control. On the other hand, the Pi output antenna loading capacitor was easy to fit so that the control shaft aligned with the ANT TUNING control.
The original component layout
Keying is achieved with a key jack in the cathode of the second 6V6 RF multiplier/ driver stage. The control grids of the two parallel 807s in the PA are initially biased to â€“48V derived from the two 6.3Vac windings and one 5Vac. transformer windings in series using a voltage doubler rectifier. This gives the PA anodes an initial standing current of 100mA during key up. However the drive from the first key down period tops up the bias to â€“85V, resulting in a more reasonable standing current of 20mA
Finally The early start up of this transmitter went relatively smoothly. The main problem was VFO stability with unacceptable jumps in frequency. I had chosen what looked like a good quality valve base from the original transmitter to build the VFO. Unfortunately, it appeared that some valve pins made inadequate connections through the valve base. Cleaning and tensioning the valve pins improved things. A partial rebuild of the VFO circuit rebuild was also required. The design would have benefited from an extra stage of VFO buffering but this was not possible because of space restrictions. I tried to only use components available in the late 1930s and early 1940s. The only area where this was a problem was the use of valve rectifiers in the power supply. These would have would have required additional heater windings on the AC supply transformer and taken up additional space. Under the circumstances I felt that solid state rectifiers were the only option. NOTE  Early transmitter power ratings used DC power input to the power amplifier anode (HT volts x anode current). A transmitter rated this way, with the PA biased in class C, would give a maximum RF output of about 40watts. Peter Dodd G3LDO
Band Reports Band reports are a bit thin this issue - many thanks to Graham for this contribution I have had 2327 QSOs in 2012 so far. In April I had 518 and in May to date, I have had 202. Admittedly, most are contest type QSOs. Â Notable DX worked in April /May is as follows: Â 4L1BR on RTTY on 40m 5C5W on RTTY on 20m 6O0CW on CW on 15m 7O6T on CW / SSB on most HF bands 9M0L on CW on 40m, 20m & 15m A61ZX on SSB on 20m HL2LUA on CW on 20m (Long path evening QSO) HS0ZIQ on SSB on 20m
LU9DPM on CW on 10m PY0FM on CW on 10m RI1ANF (South Shetlands) on CW on all HF bands VK4WR on SSB on 20m VP5/KE1B on CW on 20m Â 73 Graham G4FNL
Â Club Member Profile G3NDJ My first introduction to amateur radio was about 1943. l was a trainee engineer working at RCA (the film equipment people). One of my colleagues was a licensed amateur who invited me to his home to see amateur radio demonstrated. The seed was sown. I joined the RAF in 1946 and I met a local amateur who lived near the camp. Inside the shed in his garden was a fine array of radio equipment along with some closed circuit TV that he was playing with. Outside there was a tower with a 3-element Yagi. Oh boy this was good stuff. Unfortunately, my service was for a 5-year stint. This involved a lot of traveling, including touring the Middle East, so my new interest in amateur radio had to wait. After leaving the RAF I trained at HMV as a TV engineer and was later in charge of a service department in Kent. By this time l was married to Vicky. One of my engineers was Tom G3BGU - he was my mentor and helped me with info to pass the amateur radio exam to gain my license. This I did in 1958. Chris G3NDJ
St Dunstan’s Ralley Hi All, As you all may know by now from last February, St Dunstan's at Ovingdean has now been renamed. It is now Blind Veterans UK and it has a new callsign, M0SBV(Service Blind Veterans). To that end, the Blind Veterans A R S is to get some new radio equipment and to help raise funds, I have organised a radio and computer rally for them on Sunday 29th July at Ovingdean. If anyone would like a table, which cost £10 each, please let me know and I will send a booking form. Spread the word - there could be some good bargains to be had. Now for the hard bit! I would like about six or so helpers on Sunday from 0930hrs as marshals, making tea, hot dogs etc for sale (all facilities for that will be there) and also to help set up on Saturday. If you can help me out, please let me know, that would be great. As this is a new venue, we need sellers and buyers to support this worthy organisation for our blinded ex-service men and women. If successful, we can do the same next year. Thank you very much. 73, Eddie G0ECW
In Conclusion - Electronic Ragchew I am trying to persuade all of our club members that the electronic version of Ragchew, either as a pdf file to download or the excellent page-turning on-screen version that we have available on the club website, is the way forward. I would like to ask those of you who enjoy this format to tell the other club members about how quick you are receiving this - and yes we will have a paper version in the next week or so but we have to wait on others having the time to print and distribute it. Most important as I am writing this in Liechtenstein, a printed paper version simply would not have happened! Phil G4UDU
Club program, activities and dates for the diary June 13th 80 mtr club championship CW contest 20th Discussion evening 21st 80 mtr club championship SSB contest 27th Surplus equipment sale July 1st Monthly Breakfast meeting at The Goring Café 9am 2nd 80 mtr club championship CW contest 4th Talk by Adrian G4LRP, DF hunting for work and pleasure 11th Discussion evening 11th 80 mtr club championship SSB contest 18th Annual club Foxhunt 19th 80 mtr club championship DATA contest 25th Planning for Fire Brigade open day, plus possible talk August 1st Talk by John G3WZT on Vector network analysers and their uses 5th Monthly Breakfast Meeting at The Goring Café 9am 5th Special Event station at Selsey Lifeboat Station GB4SLB 8th Discussion evening 8th 80 mtr CW Sprint contest 15th Planning for Lighthouse Weekend-discussion 18/19th Special event station at Shoreham Lighthouse 22nd Club Barbeque Evening (no meeting at the clubroom) 23rd 80 mtr SSB Sprint contest 29th Planning for SSB Field day contest September 1st/2nd SSB Field Day contest 5th Talk by Bob G3VXJ “ SOTA “ How to reach the top 12th 80 mtr SSB Sprint contest 19th Annual club Construction Contest 26th GX3WOR On the Air evening 27th 80 mtr CW Sprint contest
Items for Sale If you have any equipment you would like listed here, please send me the details via email.
Ragchew May June