Hi Terry,
Am 10.06.2012 23:38, schrieb Terry GW0EZY:
Stefan
Thanks for
your interest in my LF
preparations.
Yes, there are not many transmitting newcomers on the band and what you
tell sounds serious.
I was lucky
earlier this year to obtain a
Decca 5501 (Many thanks Mal). It is now tuned to 136 kHz thanks to the
very
helpful and detailed notes posted on the internet by Jim M0BMU, Dave
G0MRF and
Mike G3XDV. The antenna is an inverted L with one end in a tree 22 m
high about
90 metres from my shack with a 13 m mast.
That sounds very nice. For LF, my favorite measuring device is the
tuning meter of M0BMU. Probably you know the pdf / article. It is very
helpful to accurately find the resonance and match the impedance to 50
Ohm.
Do you have a good ground conductivity? At least that sounds all most
promising so that i will see you on the band.
Will try to
get a neighbours
agreement for a 300m loop.
Vertical or horizontal? I can confirm from a test what i read about the
very poor performance of horizontal loops on LF. So better use the
aerial as a wire against ground. However a vertical loop could be nice
to play with. But the vertical will be much better i expect!
For
loading, two large clear-plastic
“mixing” buckets giving 800 mm height and 300 mm width. I should be
able to get 200 turns using a combination of Litz wire (thanks Mal) and
Flexweave. Not sure if it will give enough loading or what the variable
tuning
arrangement will be.
Well, my coil is also 300mm in diameter and i also have a inv-L
antenna. But mine is "just" 70m long and i only need about 160 turns.
So you will need less i think.
A lot of
work to do before LF Txing, so it
was good to have the 7 MHz X-Band QSOs this weekend with Mal on 136 and
500 kHz
to give me a try at LF ops. If any other LF op can do X-Band I would
like to
test and there are probably other LF listeners who might like to try an
X-Band
test. If you can do X-Band to 40m or other HF band I’m sure you would
create
a lot of interest as your beacon is probably one of the first amateur
signals
new LFers hear.
Yes, i should consider to arrange a HF station near the LF system. But
it's not so easy since antenna wire cannot simply be switched to a HF
tunernand PA by a relay. I would have massive HV problems. A separate
HF receive antenna would be an option...
Good idea, thanks. Ah and yes, good to gain new newcomers! :-)
All in all it sounds as if you will be one of the active stations i
mean active of those who CAN be active. Looking forward to some traffic!
73, Stefan/DK7FC
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