N1EU wrote:
>
> Generally true, except my 75A4 kicks the Omni 6's butt
> all over the neighborhood on 10m. It's that darn
> silicon of the clocked variety, esp in marginally
> grounded/shielded/decoupled environs ;-) . . .
> unless, you're a bird lover that is
Tentec does need to apply shielding to their radios. I think a good set
of shields surrounding oscillator, signal, and synthesizer modules would
do a lot good for making them quieter. Of course the Triton with it's
dial string has fewer oscillators and n0 clocked silicon to add noise
and spurs. When I lowered the second mixer noise in my 75S3B, I
discovered many tweets that had been hidden.
I recall that for a long time after other radios appeared the A4 was
preferred by the serious EME operators as simply working better. Low
phase noise had to be it, because its mixers aren't quiet.
Some of these years, I'll have a show down between the tubes and the
Corsair II and maybe something I've built to see which hears the best
with a 2m converter. Checking for MDS instead of noise figure tends to
show up phase noisy receivers and the tube stuff around here fares well
or better than the radios with all their features and memories. Though
it may take building a triply shielded generator to keep the leaks
through the lack of shielding from being heard. I'm in the process of
adding another shield to my 50 MHz crystal controlled generator. One
layer of shield isn't enough.
73, Jerry, K0CQ
>
> 73,
> Barry N1EU
>
> --- "Dr. Gerald N. Johnson, P.E." <geraldj@ames.net>
> wrote:
> >
> > Naw, silicon is quieter than tubes, more gain per
> > device too.
> __________________________________________________
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