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Old October 6th 06, 09:21 PM posted to rec.radio.shortwave
Telamon Telamon is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 4,494
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In article om,
wrote:

Telamon wrote:

What equipment are you using to make the IP2 and IP3 measurements?

Can you share the comparison data you took on the units?

-- Telamon Ventura, California


I didn't do the tests, a graduate (PHD) engineering student I know
ran the tests for me. I will ask for the exact equipment used.As for
the exact data that will take a while, my "ham shack", communicaitons
room radio room is packed in boxes for the renovation.

I know the people at a local EMI certification lab, full screen room
etc, and I am hoping to run some tests on all of my active antenna,
the "soon" to be completed WL1030 and the 1530.


Well for the measurements to be meaningful the test conditions must be
known. You must (best) know the tone frequencies and input levels along
with the output tone levels and the levels of all the intermodulation
products you want to report on.

IP2 and IP3 are specifications that are higher the better. If I'm not
confusing you with another thread I think you mean a comparison to the
ALA1530 you you writ "1530". The ALA1530 has very good specifications
and to quote this page:
http://www.wellbrook.uk.com/ALA1530.html

"The Broadband Loop has been specifically designed to reduce
intermodulation products to a minimum. The second order and the third
order intercept points are typically +70dBm (IP2) and +40dBm (IP3)
respectively. Thus the level of the intermodulation products are
generally below the atmospheric and man made noise."

These intermodulation numbers are huge and I don't see the point in
working to get higher numbers than these. I could say that numbers
higher than these are not important unless you sit by some transmitter
in the passband of the antenna/amplifier.

I am I off base?

--
Telamon
Ventura, California