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Old July 27th 08, 11:35 PM posted to rec.radio.amateur.antenna
John Livingston John Livingston is offline
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First recorded activity by RadioBanter: May 2008
Posts: 3
Default MA5B background noise

Andy wrote:
"John Livingston" wrote in message
...
Andy wrote:
I have managed to make an mp3 up. The first 10 seconds is on the Cobwebb
followed by another 10 seconds on the MA5B beam pointed in there
direction and then back and forth every 10 seconds. The click is the
antenna switch clicking over.

It can be found here.
http://www.hobby.pwp.blueyonder.co.uk/ma5b/ma5b4.mp3

If anyone needs to here a clearer one let me know, but it will be best
after the contest has finished.

Andy

This sounds to me as if the MA5B has a very high angle lobe which the
Cobwebb may not. More galactic noise in proportion to the wanted signal?

John



Do you think the 2m/70cm collinear above the beam could cause this?

Andy


Quite possible. The influence of all large metallic objects in the near
field of the antenna will have a marked effect on the polar diagram. Try
removing the collinear to see what happens.

John