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Hello all. Just finished assembly and adjustments of a QCX-40. Set the S-meter ON and noticed that the volume control interacts with the S-meter reading.
Just would like to ask if this is normal behaviour.
Thanks.
73 de VE3MIZ

I should explain: Increasing volume level also increases the S-meter reading.
So far I am just using a signal generator and attenuator. Not sure what happens with "real" signal, coming from the antenna.

Same thing happens with a “real” signal. The S-meter is taken from the audio circuit since there is no IF, and it definitely varies with the volume. Honestly, I don’t find it useful, other than the fact that we all seem to be obsessed with S-meters, nor is it needed. My experience with this radio is you can either read signals or not. When I tested mine I could hear a signal down to -130 dBm, although to actually copy the signal it would have to be a bit more. That works out because the typical “quiet” noise floor is ±-108 dBm, especially on the lower bands.

73,

Charles -NK8O

Hi

Yes - it's normal.? Page 96 of the manual:

"The S-meter reading is indicative only, it does not have any highly accurate meaning. In any case
the audio sampled by the Analogue to Digital converter is after the audio amplifier gain stages so
the amplitude depends on the receiver gain setting."

73
Rod
G0VKX