The Omni C is just a Triton on steroids. Nothing was added that would
increase the noise level. The front-end was improved for better
selectivity, the ability to select between IF filters and audio filtering
with 3 bandwidth choices was added. The Omni C was the last of the Triton
linage however. The newer rigs came out with double conversion and
intregated circuit IF stages which added more noise. This started with the
Corsair and a tone control was added to help compensate for the hiss.
Later, in the Omni 6, dsp was added to help reduce noise.
So as you can see, every "improvement" has it's price. The quietest
receiver is a crystal set then the regenerative receiver next, the direct
conversion and finally the superhetrodyne. After that, every conversion
stage adds yet more noise until you end up with a quadruple conversion
receiver with such a racket, only dsp can make it bearable to use.
With a single conversion superhet like the Triton/Omni D etc. one can
"Hear a signal through the band noise" instead of "Hear a signal IN the
band noise". With direct conversion receivers, band noise seems to totally
fall away.
Try this experiment. Unhook the antenna from your rig, crank up the audio
gain and what do you hear? Do you hear a loud rushing sound? When doing
this with a Triton or Omni D you don't hear much of anything. Try this
with a newer rig, no fair using filters, what do you hear? Don't give me
that stuff about how that noise goes away with the antenna connected
either. That noise mixes with your desired signal. CW sounds ok at first
but listen close....Do you hear the fuzzy sound around that sine wave?
That's why you can't get no satisfaction. The fuzz causes "listeners
fatigue" and often goes unoticed.
73
On Mon, 16 Aug 1999 zeitler@ibm.net wrote:
>
> >I wonder if the Scout has the same such characteristics....
>
>
>
>
> Or the 546 Omni C?
>
>
> 73s
>
> Lane
> Ku7i
>
>
> >
> >William Lee N5WRX
>
>
>
> --
> FAQ on WWW: http://www.contesting.com/tentecfaq.htm
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>
>
Steve Ellington N4LQ
N4LQ@IGLOU.COM
--
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