G8AFN wrote:
I tried to send this message 3 times last week it apparently got held
up as I had started the subject line with the word "help" the software
at Blacksheep thought it was some sort of command but could not act on
it. Hopefully with a more sensible subject line we will be alright
this time.
I wonder what other 'commands' we might accidentally use?
I have been investigating my receive signal to noise ratio, which
seems to be about 20 to 30dB less than many people. [huge cut]
Peter,
It looks to me like you have a local noise source. The simplest way
to check this is to build a directional antenna. This could be a few
tens of turns of wire about 1m in diameter, tuned by a few hundred
pF, and coupled via two or three turns to the Rx. You can then do
three tests:
1) Rotate the antenna to see whether your S/N improves (or even
gets worse).
2) If the noise appears directional, use the antenna to get a bearing
on it.
3) If you have a 12V Rx, take your receiver out in the car with the
loop antenna and see whether you can get a much better S//N at
locations away from home.
Another thing to look at are the Loran lines. Do you see them clearly
on a spectrogram? If not, you probably have a noise problem. As a
guide, I can see them only when my neighbours are not playing
computer games or watching their widescreeen TVs.
Good luck.
Mike, G3XDV (IO91VT)
http://www.lf.thersgb.net
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