A couple of tests on 73kHz have flagged up a possible problem on
ther band.
I transmitted for some of the evening of Monday 4 Oct on 71.91kHz
but was not audible with G3YXM. I also listened for Dave's signals
but could not hear him either. This is despite us having a QSO last
winter and my antenna system being much better since then.
My sked with G3LDO also failed both ways on Tuesday morning.
previously I was able to copy Peter consistently at 549. Although he
had never heard me, my 136kHz signal has gone up 2 s-points
since our last try on 73 so I had a reasonable assumption that it
would be easy.
A possible answer is that the Rugby signal on 73.0kHz appears to
have bigger noise sidebands and is raising the noise floor at 1kHz
or so out. A quick test with a directional antenna reduced the noie
floor but I still could not hear Peter.
We are carrying out another test tomorrow morning (6 Oct) between
0700 and 0745UTC, and I will be transmitting a beacon this evening.
Has anyone else noticed increased white noise on 73 recently?
Since my activity on the band is very sporadic and my antenna
changes in between it is difficult to do a proper comparison myself.
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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