Hello Graham,

Thanks again for the reception overview.

Lack of reception at the start might have been due to severe static.
See the attached Linrad overnight plot of VO1NA.

I have changed the front end filtering for the RTL SDR V3. It now 
consists of a double tuned band pass filter with a -3 dB bandwidth 
of about 12 kHz (loss 6 dB), followed by a tuneable pre-amplifier 
with a gain of 20 dB.

I have measured the sensitivity of the RTL SDR V3 dongle. At 477 kHz 
the MDS is -121 dBm in a 500 Hz bandwidth. At 100 kHz the MDS is -93 
dBm.

73,
Roelof

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