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Old April 29th 04, 08:34 AM
Dummy
 
Posts: n/a
Default Antenna radiated spurs

I'm having a two-way radio. One wide-band antenna was hooked up on a
spectrum analyzer. Video BW and RES BW was adjusted to 3khz and 1kHz
respectively at spectrum analyzer. Span was 300KHz.

When radio was being keyed up, spurs could be seen at around plus
minus 32Khz and 62khz. However, the amplitude were quite low, about
-65 to 70dBc. I was wondering what caused the spurs to appear. If
radio was connected directly to spectrum analyzer, this problem could
not be seen.

When radio was transmitting to different load with different VSWR (up
to 8:1), no spurs were seen. Spurs could only be observed while using
antenna. Could the VSWR of antenna be worse than 8:1? Just could not
figure out the source of the spurs. Please help.