Rob,
You might well find it useful to build an RF ammeter and (if you have an
oscilloscope) a Scope Match. See Chapter 10 of the Radio Communications
Handbook.
I have had the same problems with earth resistance as you have. In my case,
multiple earth spikes near the feed point do not seem to do much. Their total
resistance when connected in parallel is about 24 ohms, but the resistive
component of the feed impedance is about 150. I am experimenting with earth
mats, but think I will probably need to improve the insulators at the high
voltage points, and move those points further from the trees.
John
F5VLF
On 27 Jan 2012, at 20:52CET, Rob, M0DTS wrote:
> My TX is now working all be it fairly QRP 90W ;-)
>
> Antenna is 53m horizontal at ~9m high.. a droopy 'T' single strand copper all
> the way.
> I'm also receiving on this antenna too with much better results than the loop
> i have.
>
> Problem is going to be getting enough routes to earth, my last attempts were
> getting ~1A antenna current with the same power but it looks much worse on
> G4WGT's grabber than last time so i guess it's less than 1A.
> Will do some more improvements over the weekend.
>
> Rob
> M0DTS
>
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