[Elecraft] Noisy K-3 Receiver

[Graham Kimbell (G3TCT)]

This statement (If you run RF GAIN wide open the receiver will sound noisy
and you are limiting your dynamic range)  is only true for the bands where
the
band noise is high, but on the higher bands (eg 6m), the band noise is only
a little higher than the receiver noise (and maybe not at all if you don't
have an external preamp).

And on my K3 (as reported previously with f/w 3.63) backing off the rf gain
*reduces* the S/N because the front end noise no longer overcomes the IF/AF
noise. There's lots of noise generated in the later stages of the rx, which
can still be
heard with the rf gain backed off.  This does not appear to be a function of
the AGC settings.

This is a major irritation that has only surfaced with recent firmware
changes - the problem wasn't there in f/w 3.27. Other receivers I've used
keep the S/N constant with the rf gain backed off presumably because they
are reducing the IF gain further back in the rx.

And let's be clear I'm NOT talking about 160 or 80m where the band noise may
be many dB above the receiver front end noise.

Graham
-------------------------------
Previous comments include:-
> If you run RF GAIN wide open the receiver will sound noisy and you are
limiting your dynamic range.

and

>I find it hard to believe that the K3 receiver is actually noisy, in the
sense that it is generating noise internally that makes it harder to hear
weak signals compared to another RX. Those MDS figures can't lie, surely?