[hpsdr] Odd Mercury behavior

[Werner Hlawatschek]

Hi Frank,

I noticed sometimes the same effect you described. It is absolutely random and I couldn't find a way to reproduce or force the effect. I don't think it is an  oscillation of the pre-amplifier. What helped in my case is to shut down PowerSDR program and run initozy manually ( sometimes two times in sequence) and then start PowerSDR again.

Don't ask me the reason why, but it helped in my configuration and the boards keep on running flawless for days. I have two Penny/Mercury sets, one only for short wave and the other I use for VHF with transverter. The effect occurred only with the first one. Each set has its own computer. I had not the time to look deeper in this issue and interchange hardware between the two setups to insulate the problem.

73, Werner, DL2JA 


Hi All,
I'm noticing something new with Mercury. I would guess the input amplifier is going into oscillation. Sometimes lasts a few seconds. The broadband noise floor comes up about 50 dB. This even happens when the input is disconnected. The antenna is never connected when the radio is off and always have a 6 db pad on the input.
I looked at the board under a microscope looking for bad connections and also replaced the bad input relay. It hit almost 90 today so was motivated to solder a loop of copper tube to the heatsink pad undder the A/D.  It also runs pretty hot. 
Anyone ever notice this raise in noise floor? 
The power supply is a linear. Frank WA1GFZ

 
 








      
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