Thanks to Dave (above) I/we enjoyed a protracted but largely very successful day out. My summary below while I can still remember it all!
What a day.....70cms, 13cms QRP, 3.4GHz experiments 5.7GHz DATV and FM TV , plus a visit from the MOD Police!
As planned I set up at Burton Dassett Hills just south of Gaydon on the M40, the site of my successful amplifier tests on 3.4GHz a couple of weeks ago. Although I had successfully run-up my new big PA for 70cms yesterday, as it needed up to 750Watts of DC input I left it and the necessary generator at home and opted for lighter loads. Despite this the days activity consumed 42A/Hr from my leisure battery and another 6A/Hr from one of my Li-ion laptop packs (10.8V 98W/Hr) the latter being good enough to run my Portsdown4 for around 5+hours and which allows for moving it around between tripods/parcel shelf etc.
So to 70cms, easy contacts both ways with Dave G4FRE but despite protracted trying nothing was seen from Arthur or Steve further south. This was a bit surprising given their power and the relative distance, but it was no-go. Upward to 3.4GHz where the previously tested new Toshiba amp was fired up to confirm signals. Interesting that they were not quite as high as previous, but having set the bar, I moved on to testing my Stealth (Purple heat-sink) amp and establishing suitable drive levels for that. Tests complete on the amps, I moved on to try firstly a BSB mini-dish fed with a bi-quad, this was reported as about -10dB on my 16-patch flat-plate. A similar test with a double bi-quad yielded similar signals but a lot less windage. Useful for the future, I can leave something at home.
As it was also a u-wave contest day Dave and I used our Langstones to exchange 5/9/001 on very strong SSB signals. Upwards to 5.6GHz and my 'somewhat hopeful but worked really well' solution to receiving worked too, again Dave provided feedback on the strength and shape of my DATV signal. Two-way DATV and one-way (my TX to Dave) worked on NB too. As the gear was on the tripods we both connected up our 5.665 drone FM tx/rx and we exchanged nice quiet 'P5' FM pictures. At this point I lowered my 70cms beam and swapped it for the 13cm 46ele loop-yagi. This thing goes like a rocket and copy was nearly achieved with what turned out to be a few mW leaking through my U/S 13cm mini-pa. Well it worked last time I used it..... So we tried JUST using the pre-driver, one of the eBay 50MHz-6GHz do-it-all amps. And it worked – 50km with a MER of 14 from 50mW. That's another one to add to my G-QRP club tallies
But what about the MOD Police visit? Someone early on in the day reported me as looking like I was undertaking 'suspicious activity' so he was duty bound to investigate. Evidence of who I was (drivers license and car reg) was duly logged, investigated and given the all-clear. (
https://en.wikipedia.org/wiki/MoD_Kineton) Several interested people asked what I was up to and nobody suggested that I used my mobile phone instead
Despite the sunshine, which was very pleasant, there was a chilly breeze most of the day, necessitating TWO woolly hats, a sweatshirt, armless fleece and an anorak over the top of it all. I still wished I'd packed a scarf.
Kit tested, hardened, faults found, kitlists needed and those blasted RP SMA used on the FM 5.6GHz gear need changing, although a rummage through the multiple connectors boxes produced one workable solution.
Gareth
