1600S with 10mhz spurs

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msingewald
Posts: 40
Joined: Sat Mar 29, 2003 4:16 pm

1600S with 10mhz spurs

Post by msingewald »

Hello All,

I have an IFR 1600S which I have had for years. Suddenly I am now getting spurs on the Spectrum Analyzer every 10mhz. If I set the scan to 50 or 100 mhz, I don't see them as I assume they get lost in the large resolution bandwidth. When I get the scan down around 500khz, I can see the spur to the side and if I change frequency to center the spur, it disappears when it gets close to center. This occurs regardless of input chosen and whether or not an antenna is connected.

Another issue, which may be related or offer a clue to the other problem, is that when I run the tracking generator, the output amplitude is going up and down as the frequency sweeps. I checked this with a scope hooked up to the output. I was having a hell of a time trying to tune a can when I decided to check this out.

It does pass the self tests, however, one time test #17 (I think it was a tracking test) failed. Leaving it off overnight seemed to make the problem disappear as it passed the next morning.

Can anyone offer any advice? I re-seated all of the cards and rf connectors. We put the output of the power supply on a scope and it seemed clean.

Anything else to check for?

73,

Michael
N1PLH
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