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Old 3rd Oct 2019, 4:34 pm   #126
Junk Box Nick
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Join Date: Jun 2011
Location: West Midlands, UK.
Posts: 1,571
Default Re: Antenna recommendation for 40 and 80M bands

I have been monitoring this thread from the start as in a way, with no aerials, like the OP I am starting from scratch.

Way back when in the days when I first got going on HF I was still living with my parents. My budget was limited, aerials were near the end of the garden whilst the 'shack' was a corner of my bedroom at the front of the house. I put up a couple of inverted Vs but as I already knew that simply connecting balanced aerials to coax was a bad idea - and in any case was expensive given the run required and my limited means - balanced feeder was the sensible (and elegant) way to go.

I'd considered other ideas, like verticals and inverted Ls but this meant matching units near the base of the antenna, which would have in turn meant remote control, putting in a ground system which might not be that efficient, plus the dreaded cost of the coax. The problems of earthing discussed earlier in the thread were unknown to me and so never considered.

Feeding the inverted Vs with open wire feeder presented practical problems installation-wise that my parents wouldn't have tolerated but using more manageable and relatively unobtrusive 300ohm ribbon feeder was possible. A bonus was that I had been given some at some point so adding to it wasn't going to be costly. This was solid ribbon but it was around the time that the effects of damp on ribbon were being discussed in Rad Com and I spent many hours painstakingly cutting windows to some dimensions described in Technical Topics.

I built the Z-match coupler described in the RSGB Radio Communication Handbook (4th Ed) - see the attached scans. I had been given a large two-gang wide spaced variable capacitor which did for the split stator unit and I constructed the coils and placed the components precisely as the diagrams. The unit was constructed on an open L-shaped chassis.

I didn't have anything as exotic as an SWR meter. I simply tuned up the all-valve transmitter and adjusted the Z-match until I got the correct indications on the transmitter meters.

How efficient it all was I've little idea. However, I made plenty of contacts including maintaining regular skeds with the US on 20 and 15 metres and had lots of enjoyment.

I still have the unit and am considering a stealthy 40m dipole fed with open wire feeder (different house and no parents to upset!).
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