I hope the Wimo guys can claim for this from their courier as I need another one!
The guys from Wimo have been really quick on email and kindly sent out a new boom to fix my incorrectly packed antenna. This arrived at the Scout site on Saturday. The problem is that the box had a neat cut round the centre and the new boom is bent like a banana in two axes.
I hope the Wimo guys can claim for this from their courier as I need another one!
I took a closer look at the remaining parts to build the last yagi and found two potential problems. One is easy to solve – an element without a hole through it which I re-drilled in a flash. The second problem is not so good. The Driven Element has a tag on one side which I assume is used to align the elements and ensure they are all driven in phase. The problem I have is that I can’t align this DE with the other three in the stack without turning it round backwards! Three of the antennas have the DE tag on the left when the connector is facing forwards, whilst the final one has it on the right. Do Wimo produce the DEs in different orientations? Or has the tag been placed on the wrong side? How do I find out? I can’t use an ohm meter on a folded dipole…. Answers on an email postcard, please
I had an interesting discussion with Frank, M0AEU about the Gilwell Park radio station this week and have been playing around trying to design a station that will be useful for the Scouts and possibly double up as a contest site in the Scout close season. The rules for the station are simple – no wires in places where the scouts can get at them!
That doesn’t preclude temporary antennas for contests. I have done a screen grab of the site from Google earth and marked up some preliminary ideas.
The site has changed a bit from when this image was taken and the building outlined in blue has been removed and replaced with another one that is a different shape. The radio shack will be in the new building at the spot marked with the arrow. My initial thoughts are to have the following permanent antennas:
There is a commercial tower on site, about 90ft tall marked T1. My current plan is to have an HF triband yagi, plus 6m yagi on this tower. This tower would also have a side arm with halyard supporting inverted V dipoles (160, 80 and 40m, marked in purple ends >20ft above the ground). These are oriented east-west at the moment, but I am unsure of the effect of the metal roof blow them. The side arm could also hold a V/UHF vertical.
The second tower, T2, is a 40ft crank up mast with a decent sized stub mast on top. This will be the VHF mast supporting yagis for 2m and 70cm. I also have a butternut HF2V vertical antenna for 160/80/40 that could be hidden in the trees at “Bnut” to provide some low angle radiation on those bands.
This should be a fairly straightforward install as I have most of the kit to do this already.
The remaining markings are for temporary antennas that would be set up for contest use. The two green circles (rough scale to include radials) could be full size verticals for 40 and 80m. The yellow dashed lines are along thick hedgerows and could be used for reversible beverage antennas. The 800ft length would be to central America/Japan which makes sense, but I am not sure whether it is worth the effort to install a 400ft one running N/S. Is it worth having an Africa beverage? As you can see form the picture there doesn’t seem to be an easy option to install a North America beverage unless it runs across open land.
So, play fantasy radio station with me. What would you do on this site and why?
Here's a shot of all the Clifton ARS antennas at dusk, showing the 9 element interlaced 50 and 70MHz yagi in the foreground, 144MHz 9element in the middle and 15 element for 432MHz on the cherry picker at the back.
The 144MHz operating tent and 9 element DK7ZB yagi at 10m AGL.
G3JKY and G4TJE in action on 50MHZ
432MHZ yagi on a cherry picker. That makes life a lot easier. Must get another one for future contests!
Last weekend was VHF Field day (FD) throughout most of Europe. As usual I was out with the Clifton ARS near Detling in Kent (JO01HH). I provided two stations for the contest. The 50 and 70MHz station (restricted section) was based on my heavily modified FT-847 running 100W on 6m and about 70W on 4m to a dual band yagi at 10m AGL – this station was on the air as G3JKY/p. I also provided a TS-2000, solid state amplifier and 9 element DK7ZB yagi for the 144MHz station which operated under the club call of G3GHN/p. The only technical disappointment was that the2m PA would only produce about 220W in the field where it does 325W at home – I put that down to long leads from the generator introducing voltage sag. Otherwise everything was assembled in about three hours and we were on the air no problem, which makes a change!
G0GTO and G3BSN provided a very smart cherry picker and a full station for 432MHz, that they ran as G4FAA/p.
I spent some time on 6 and 4m, and the conditions were fairly spotty with minor SpE openings on both days. We did better on 4m than in previous years, which means that 56 Qs was a reasonable return, but well down on the leaders who seemed to get much better Es than we did in the south east.
The 6m score was down on last year as there was less DX. We weren’t that far off the leaders on that band in Q total, so our position will depend on how well we did on Es compared to our rivals.
2m was a major disappointment. With only 130 QSOs this was a terrible return. Apart from being a little under powered for the open section the gear was fine and on my visits to the station I worked OZ and EA telling me that we didn’t have any electrical faults. I think the problem is rather that the operators on 2m are more DXers than contesters so they spent a lot of time tuning the band looking for people to work rather than calling CQ. I need to work on the 2m station for next year.
In contrast, Terry and Phil did a great job on 70cm working the more stations on that band than the club has for several years. Having the full legal power helps, but calling CQ for long periods of time really helped boost the score, even though the band was flat. They only ran a short yagi, so with a better antenna they could have made many more mid range contacts.
No doubt I will be reflecting on this performance over the coming months and trying to come up with a solution for the next contest!
CQWPXCW Score Summary Sheet
Start Date : 2010-05-29
CallSign Used : M0BPQ
Operator(s) : M0BPQ
Operator Category : SINGLE-OP
Band : 10M
Power : QRP
Mode : CW
Gridsquare : IO91WP
Club/Team : hadley wood contest group
Software : N1MM Logger V10.2.6
Band QSOs Pts WPX
3.5 5 9 5
7 7 18 5
14 43 53 36
21 23 29 18
28 79 99 61
Total 157 208 125
Score : 26,000
Rig : TS480SAT
Antennas : Inverted L
Soapbox : That was rather fun. Lots of SpE on 10m +15m that made things interesting, but 20m was killed by the AU on Saturday evening. No DX worked (unless you count CE/PY/LU on 10m) but a really interesting trial for my new set up. That CW filter is one of my best buys for a long time!
Last weekend I finally got to spend a little time on the air during the IARU Region 1 432 and up contest. It would be fair to say that conditions were terrible, and I only managed to work 21 stations over about 3 hours on 70cm - pretty poor indeed. That said, there was some (KST assisted) DX in there but the path was supported by the DX end who were running big stacks of yagis, like DR9A at 689Km and DJ6BS at 632Km.
It doesn’t look like there is any chance of winning anything, but here are the squares worked for the record.
After returning from M3SXA’s place I fired up the remote rig set up to see if I could find some folks to work in the IARU 144/432 contest. Unfortunately I received several reports of bad audio and it looks like RF was getting into the Ethernet cables or RRC system at the radio end. This shows one major problem with the RRC/FT-847 combo – most of the radio functions are not available via the CAT system so it was impossible to tweak the mic gain or RF power settings to see if I could make things work at a distance. As my 8 month old son was sick in bed with a cold I couldn’t get direct access to the radio so had to give up. I did get access to the radio on Sunday and threw a handful of snap on ferrites at all the cables in the Ethernet network and audio chain. I also put my Ethernet network switch inside a metal box in case that was susceptible to RF. After taking the control half of the station to the remote end I readjusted all the levels including the DVK whilst listening on another RX. I sounded OK to me, but by that time the contest was over. I will have to get on for the 432 UKAC this week to try it out.
Contest Report from M0BPQ in IO91WP at 50 MHz
Lots of work to do, which is limiting my radio fun, but got time to try out my new SDR-IQ in the RSGB CC CW contest tonight. All I can say is WOW! Good selectivity and the waterfall is fantastic. I have almost an hour of the contest recorded (available on request) so I look forwards to playing with that in the future to see which settings are best!
Again a big gap between posts.
A few notes on recent radio activity by Steve, M0BPQ.