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Receiver - QRP Labs #rcvr #vfo

Bill Watkins
 

Hi,

I have the qrp VFO kit.  It's working properly as confirmed by scope.  I have the qrp receiver kit.  I'm trying to learn how to work it.  
The vfo is working and connected to the receiver as suggested by the qrp manuals and assembly.  It is running on clean 5v supply.  The multiplier is set to 4.
The receiver is running on the same 5v, including the pa.  It is connected to an antenna tuned for 40 meters, and the bpf is 40 meters.

Last night while working with it, tuned to 7.069.1 I was clearly receiving NOAA weather which I thought was transmitted at 162.400.  

Why?

I can't find an answer.  I apologize ahead of time if its a simple answer and I should get it. 

Regards,

Bill
K0WHW 

@CurtisM
 

Bill

Mixers can create spurs, and direct conversion receivers have been known to do funny things. I take it only happens when tuned to the frequency you cite? Possibly it is bypassing the bandpass filter, and coming in via the wires from the power supply. Filtering these wires by wrapping around a good RF ferrite might help. If you can copy some 40 meter signals that would convey receiver is working some. Another possibility is the vhf signal is being received on one of the circuit boards as the antenna, then shielding could help.

73 curt