The aerial is a half-wave dipole for 80m fed with twin feeder. My garden isn’t long enough to squeeze 132’ of wire in a straight line so the ends are folded down. The centre of the dipole was only at about 22’ agl, nowhere near high enough for the system to be an effective radiator. It performed adequately but that’s all.
Time for a re-think. I’ve managed to get the dipole centre up to around 30’, still not high enough but certainly better. This afternoon’s little job is to make a coax balun although the poor weather means it probably won’t get installed today.
The aerial is now certainly a better radiator on 80m & 40m, but receive noise is still a problem. Next door have a noisy TV, it may be plasma…the work of the devil! Unfortunately my neighbours are unapproachable so I need to deal with the problem on my side of the fence. The RF noise next door’s TV generates makes 80m difficult to use in the evenings. I’ve treated myself to a noise canceller (MFJ1026)but I’ve not tried it out yet, I just hope it works!
MFJ1026 Noise Canceller
This little box works by mixing signals from the main station aerial with signals from a ‘noise’ aerial – an aerial that is aligned to pick up the interfering noise. The phase and level of the interference is then altered by the box in a manner that allows it to cancel out the noise received by the main aerial = much reduced noise. That’s the theory, we’ll see.
My main interest is using low power (2-3 watts) CW (morse) on the 40 and 80m bands. Winter is a good time to play radio, hopefully my tweaked aerial system will pay dividends.Apart from the noise canceller, my main station will remain unchanged: Yaesu FT817 transceiver fitted with a narrow CW filter, and a Bencher squeeze key. A ‘T’ Match ATU is used to optimise the match between transceiver and aerial system.
Bencher Key FT817
My FT817 has a microphone but it’s rarely connected – it just gets in the way!
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