Re: FDM DUO INCREDIBLY NOISY!!! #fdm-duo

m7mcqio83ro@...
 

Okay, so I'm home and have tried the suggestions. Here's the answer to your comprehensive help Neil...

What level in dBm does the display show with no antenna connected and with it connected?
-120dBm

Any sign of the PK indicator showing? If so, does enabling the RX ATT menu 1 make any difference?
NO PK INDICATOR

If the PK indicator is NOT showing, then try these:

Does the noise level change if you connect the antenna, or is it bad even with nothing connected? 
NOISIER WITH ANTENNA CONNECTED

Does it change level if you select antenna 1 or two on menu 31?
THE UNOCCUPIED ANTENNA SOCKET IS QUIET

Is anything else connected at all? (keyer, PTT out, ref in, USB etc?)
NOTHING ELSE CONNECTED. STANDALONE MODE

What settings do you see on the E1 control?  Mine has SQL OFF, AGC ON, AGC FAST, AGC TH 3, NR OFF, NB OFF, AN OFF
SAME EXCEPT AGC TH WAS 0.

How about E2? I have RIT OFF, FIL 2700, PITCH 600
SAME

I am in USB mode.
NOT CONNECTED TO PC YET

===========================================

So the AGC Threshold was at zero which produced more noise. The radio sounds much better - thanks Neil!!

It's still not as quiet as my other radios and has definitely got a higher noise floor than similar SDR radios I've had (FLEX3000 & ELECRAFT KX3). I'll keep on experimenting and see how I can improve things over the weekend.

Tomorrow, my DUO ART 120 with ATU arrives, so maybe the FDM will benefit from drawing its power from the amp? Having said that, I've had zero problems with noise before from my PSU's.

I'll keep you all posted and once again, THANK YOU!!

Tom M7MCQ

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