OPEN UNIVERSITY AMATEUR RADIO CLUB
NEWS LETTER no:42
G0OUR Affiliated to the OU Club and the Radio Society of Great Britain
Well, that’s another year almost over. Please make a note of our forthcoming 2015 AGM on Thursday 22nd January at 12.30pm. We’re in the same room as last year: Central Meeting Room 14, on the first floor. This is accessed from outside via the East Central Meeting Rooms entrance, near the shop. An email reminder will be sent nearer the time, and local members are urged to attend if they can. Subscriptions are due in January and remain at £5. Please send to OUARC, c/o F. Robertson, S1021 Venables Building, O.U., Walton Hall, MK7 6AA.
Following on from all the hard work we did last year, the new antennas are now performing well. Thanks to the OU Estates guys, the adjacent trees were trimmed back and we were able to get the tower and antennas up. We had some teething problems with the Hexbeam – it was off resonance on 15m, and we found that the insulators weren’t quite up to the job. We were supplied with a replacement set of elements, with uprated insulators. Unfortunately we had to take the antenna down and off the mast in order to fit these. However, having done so, it now works well on all six bands 20m through to 6m, and has proved to be 100% reliable. The 6m/2m/70cm colinear is also working well on the refurbished P60, as is the replaced doublet for 40 and 30m.
We have bought new guys and winch ropes for the heavy duty P60 mast, which supports the triband beam. We hope to be able to fit these replacements in 2015, when the weather improves. The 17m delta loop on that tower has broken. It’s not needed now that we have the Hexbeam, so we may replace it with a delta loop for the 30m band. Once this has been done, all the antennas should be in good shape for the coming years, fingers crossed.
In general the noise level seems to have dropped a bit in recent years; perhaps as old network equipment has been replaced. We do have some new intermittent interference sources, partly it seems coming from the new waste management research facility nearby.
Thanks go to Paul M0OOM for refurbishing the shack burglar alarm, and fitting a PIC based timer to control the sounder and strobe. This should avoid the occasional call outs that we’ve had in the past. The Security Lodge have a key so they can reset the alarm if necessary.
We had our usual pitch at the DDRC sale at Stockwood Park this year, and cleared £257.90. Unfortunately we were not able to have a pitch at the MK sale, being a Bank Holiday weekend members had other commitments. However, Paul M0OOM has had some very successful surplus equipment sales on EBay for the club since then, so funds are in healthy shape.
Adrian M0ANS reported a visit to Baldock Radio Monitoring Station in early November, unfortunately in the end he was the only member who could attend the open afternoon. This facility is Ofcom's "listening ear" on the radio spectrum: “Monitoring of the radio spectrum plays a vital role in keeping the spectrum clean for authorised users and to aid spectrum managers in their day to day work.” This was an IET organised event. We hope that more members can attend a future event.
We had a stall at the OU Club Fayre on 18th November. We had a demonstration of Software Defined Radio using our Flex 1500 SDR, displayed on a large screen. We also showed other more conventional HF and VHF equipment, along with pictures of the shack and antennas, QSL cards, and information on the club, and the hobby in general.
Also in November, we were able to purchase an Elecraft KX3 for the club. We are very grateful to the OU Club for their financial support towards this. This radio is also an SDR, although in the guise of a more conventional radio, with a front panel resembling a cut down K3. It’s amazing what has been fitted into such a tiny box. We bought it in kit form, and Paul M0OOM put it together, he said it was a very tight fit! We bought the optional internal battery charger / real time clock, and the internal auto ATU. Somehow though we didn’t think to buy batteries or a microphone for it! As funds permit we hope to add the optional roofing filter, and perhaps the 4m or 2m option. Quite how that all fits inside the tiny box I’m not sure, but it does apparently. What’s more amazing is the performance of this tiny radio, see http://www.sherweng.com/table.html, even outperforming top of the range large base station radios like the FTDX5000D (with very large price tags too). It’s interesting that a relatively small and recent company like Electraft, from California, can compete with, and even beat, the ‘big three’ ham manufactures from Japan.
Other members are reporting great results using SDRs, including Bertie G3FVO with his Kachina, and Adrian, who points out what can be done (bought) for as little as £10: “There's a good write-up on how to install the basic software for the SDR dongle at http://www.essexham.co.uk/news/realtek-sdr-pc-dongle-for-under-20-pounds.html
This SDR dongle is designed to plug into a computer so that you can watch Digital TV and listen to the radio. At the Essex Ham website (above), you will find a further link to SDR#, which seems to be a driver that uses the dongle to give you a full coverage receiver, rather than just watching digital TV http://www.sdrsharp.com/#download. There are so many possibilities, like: diversity reception, remote site operation, range / propagation tests, sniffing out ionosound systems. At only £10 a punt, I'm going to get one,” says Adrian.
Also on the equipment front, unfortunately the club’s HF linear has developed a fault, where it’s tripping out the 30mA mains RCD. We’re hoping it won’t be too much of a job to repair, but haven’t had a chance to look at it yet. The Ten Tec Omni six still has a fault on 30m, plus a few other issues.
If you haven’t already seen it, take a look at TXfactor, http://www.txfilms.co.uk/txfactor/. This is an online TV programme about amateur radio. There have been six episodes so far, and they are topical and well produced. Well worth a look.
That’s about it for now; hope to see some of you at the AGM in January. Season's Greetings…
Contact: Adrian Rawlings adrianrawlings@googlemail.com