Author Topic: Low AF output in K3-twins configuration  (Read 1162 times)


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Low AF output in K3-twins configuration
« on: 2022-10-24, 22:26:23 »
I've had a K3-twins configuration running within my house for years.
Now I seem to have very low AF at the K3-0/mini when I plug in headphones (PHONES front panel jack).  It doesn't seem to materially impact digi modes (but how would I know?).  The AF level at the side SPKR jack is the same.
I made some AF voltage measurements under controlled conditions and measured 0.5V rms at the K3 rear panel SPKR OUT jack.  However after plugging the remote RRC into that jack, the output from the control RRC SP jack is only 3 mV (-45 dB!!).  I've swapped 3.5mm stereo cables between K3 rear panel and RRC/remote input with no effect.
I don't necessarily expect the RRC remote to exactly duplicate voltages, but this is a little much.  I have fairly significant hearing loss as it is, and the low AF impacts CW/SSB operation. 
Control|Radio Settings:
Codec out gain 255
Codec input gain 18
Codec inp preamp YES

Remote|Radio settings
Audio dual-rx Yes
Codec out gain 255
Codec inp gain 0
codec inp atten YES

PS another symptom is that it used to be with the AF control at 9 o'clock on the K3/0-mini the audio input slider (on JTDX) would be about 52-53 dB.  Now I have to turn the AF control to 12 o'clock and the JTDX slider only goes to 40-42 dB.

Any suggestions?  I suspect I have a setting fat-fingered but darned if I can tell what it is.
« Last Edit: 2022-10-25, 15:02:06 by nx7u »


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Re: Low AF output in K3-twins configuration
« Reply #1 on: 2022-11-03, 18:22:01 »
I have the same problem with one of my Control RRCs, affecting the SPKR Audio.  The jack seems to be bad; if I put a little pressure on the plug, everything is fine.  If its not in the jack exactly right, low SPKR output is the result.  For now, i put a clothespin on the cable and that's enough weight to keep the connection good.  Sooner or later I'm going to have to replace that jack.

Dennis W1UE