----- Original Message -----
From: "joel hallas" <jrhallas@optonline.net>
> Folks,
>
> I seem to have a new problem with my Paragon. It transmits spurs 600 Hz
> above and below the carrier about 10 to 20 dB down from the carrier.
> This was reported to me by someone using the spectrum scope on an
> SDR-1000. I have confirmed that at least one is there on another
> receiver and the level seems about right. I can also notice the effect
> on strong receive signals. I thought it was them <g>!
>
> I will put it on the spectrum analyzer at work next week, but wondered
> if this is a known problem? I have done the "routine" things like
> tighten all board screws and reseat all connectors and master reset.
>
> Any thoughts?
>
> Thanks!
>
> Joel Hallas, W1ZR
Joel,
What was the input voltage to the Paragon? I think it
maybe sensitive to input voltage. Before I retired it,
I ran mine off of a 13.8V supply and never had any
complaints about my TX purity, nor did I notice any
spurs on receive (-40dBc spurs would surely manifest
reciprocal mixing products with strong signals which
I never saw in practice). When I put it on a spectrum
analyzer, however, it looked horrible:
http://www.dellroy.com/W4EF's-Ham-Radio-Page/Paragon/paragon_tx_spectrum.htm
I never resolved the discrepancy, but in thinking
back, I may have carelessly run the spectrum
analyzer test at 12.0V input instead of +13.8V.
I know that my Omin 6+ just plain doesn't work
at 12.0V (it needs +13.8V) and I suspect that
the Paragon may have similar issues. I had intended
to re-run the test with a variable supply, but I
just haven't had the time (not much incentive since
I am not using the Paragon currently).
In any case, I would start with supply voltage
and go from there.
73, Mike W4EF..........................................
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