Antennas (3)

M0RVB

Moving metal

Just recently I have been comparing results on 2m FT8 between the Big Wheel and the QFH. I found there is very little diference between them, and although measuring via reported strength via pskreporter is hardly scientific the varying reports between the two - sometimes in favour of the Big Wheel and sometimes the QFH - brought me to rationalise the metalwork currently in the loft. Suffice to say the Big Wheel is no more and I am using the QFH from now on. This not to say that I don't want a nice Yagi and rotator on the chimey but that is a project for another day. Now the next interesting experiment is to see if I can reach FM satellites on the QFH. It should be better suited to those.

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M0RVB

VLF ready, hopefully!

I now have two new toys, an Airspy HF+ Discovery SDR, and an Airspy YouLoop antenna. Plus I already have a SDRplay RSPdx which was purchased some time ago. The initial aim of these is to hopefully receive signals from SAQ’s 100 year anniversary broadcast. The YouLoop is in the loft and connected to some RG213 coax back to the shack. That coax was feeding the random wire for HF but as I now use the external wire the coax was pulled back and shortened. It is entirely passive so does not require any voltage supply and has a range of 10kHz to 30MHz plus VHF up to 300MHz. There is also an IP35 mini whip which was acquired some years ago and as an active device needs a supply which is achieved by a bias-tee fed from the 12V shack PSU. That antenna has a range of 10kHz to 30MHz and is fed via some RG58. The YouLoop is pointing, quite by chance at the MSF 60kHz time signal transmitter. The IP35 is largely omnidirectional. The Airspy covers 0.5kHz to 31MHz and 64MHz to 260MHz whereas the RSPdx covers 1kHz to 2GHz with no gaps (200MHz on the BNC…

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M0RVB

Finally connected the 'temporary' external wire

Things happen slowly here. Very slowly... I finally got some coax fed out through and air brick and connected the external random wire up that slopes down to the workshop so I cna use it without needing to open the shack window and feed a cable out. Experimenting, the tuner was happy on 6, 10 and 12 but less so on 15 with the rig seeing a SWR close to 3. It would tune 30m too but knocked the GPS signal to the clock off, clearly RF in the shack. I did not try lower because I then realised that, like a twit I forgot to fit the 1:1 unun! With the 1:1 unun installed outside the tuner was happy-ish with 15 but now not 12. Oh well. And it refuses to get below a SWR of 3.0 on 30m and is quite bad on 40m which is annoying, but on the plus side tuning does not knock the GPS clock off! I suspect I have managed to get an awkward length of wire so I will shorten it later on and expreiment further. Surprisingly, it is happy on 80m and it will tune 160m but that did knock the…

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