James Moritz wrote:
> John - your lack of trees is not such a bad thing on 136k, where they soak
> up a lot of your TX power.
Jim, LF,
Yes, on this point I'd agree, and it's probably why I did okay on
500kHz, up to a point.
However the lack of ANYTHING tall in the adjacent area makes it awfully
tricky to hang any respectable amount of wire in the air. I could run a
horizontal wire back the the chimney on the house, at about 8m agl, but
I try to keep wire as far away as possible from the house - a great
source of QRM.
My 8m vertical with a few sloping radials is tuneable on 500kHz, with an
efficiency of 0.5% or so, given the poor ground losses I have due to
waterlogged peat and rock, but on 136 I think I'd struggle to radiate
anything without resorting to some seriously high TX power - with all
the problems of high volts and general arcy-sparky that would ensue.
I did try the fibreglass pole at 12m but the severe weather soon saw to
that. At its reduced height of 8m it's survived all that Shetland storms
can throw at it.
To go much higher I'd need to excavate holes and form some concrete
blocks for holding guying points, and another for the mast base, and
then I might get 15-20m or so, in scaffold pole. A tower is out of the
question, for expense and visual impact. There's still nowhere for a
long horizontal top load to run to, and stay a sensible height AGL. All
in all, more engineering than I'm prepared to do, certainly at this time
of year.
Will look for more WSPR on 136.
Cheers,
John
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