Hi Joel,
You'll notice from the pictures on the link I posted that the spur
content was a function of frequency as you might expect from
a multi-loop synthesizer. You might want to check several
different frequencies just to be sure you everything is okay,
especially if you weren't careful to use same exact frequency
for your before and after tests.
Mike W4EF...................
----- Original Message -----
From: "joel hallas" <jrhallas@optonline.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Sunday, January 28, 2007 1:22 PM
Subject: Re: [TenTec] Paragon Problem -spurs on either side of carrier
> Mike,
>
> Good observation, my Paragon gets very clicky much below about 12 V. I
> am running it on a UPS system "12 V" AGM deep cycle battery and charger
> (described in my QST article in Dec 03), along with a W4RRY Battery
> Booster that keeps it at 13.8 V if I lose ac power, until the battery
> drops to 10.5 (QST Oct 05)
>
> Well, I went to measure, just to be sure, and everything was as expected
> - voltage wise. What surprised me was that the problem has now gone
> away. I would attribute it to contact resistance being cleaned up in the
> measurement process - except that previously it had the same problem
> with the TT ac supply and is now clean with that as well. I guess it
> could have been contact resistance at the main power connector at the
> back of the radio. Or the radio perhaps decided that it had tortured me
> enuf! <g>
>
> Thanks again & 73, Joel, W1ZR
>
> Michael Tope wrote:
>
>>----- 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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>>
>>
>>
>
>
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