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Showing posts from December 17, 2012


To be able to receive at 500kHz  I had to kill the 500kHz  QRM source.
Yesterday  I used my modified to 475-500kHz "RANEX"  pocket radio  to search the
 the noise at 500kHz.  That QRM was covering 500kHz for more than a week. 
Constantly  50kHz wide and stable in frequency.
This time I searched at neighbours home  but nothing found.
This MW receiver is a great noise sniffler.
There are lot's of noise sources in a home to be found.
I found an new one a CD player in standby mode.

Back at the radio the 500kH noise  was  gone suddenly..
I switched the CD player back on but that was not it.

Nothing found but QRM was gone.

Then replaced the 1:9 transformer back to the original in the K9AY rx antenna loop.
This one has a small core with high AL. 
I tested a transformer with low Al   not trifilar but "normal" wound 1:9 
 In the hope getting better result but it was no improvement.
The K9AY does not work at 137kHz it starts to work at 500kHz the signals are always weaker than fr…