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Old September 29th 08, 05:52 PM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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First recorded activity by RadioBanter: Jun 2007
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Default 2MTR/ 440 DIPLEXER

On Mon, 29 Sep 2008 15:09:56 GMT, "JB" wrote:

If you get the pigtail type you can cut of the stupid PL259 and put N males
on. I wanted to tear my hair out when I bought a unit with bulkhead
connectors and wound up probably losing 3 db in all the jumpers and
adapters.


Have you ever actually measured the loss in coax adapters? See:
http://802.11junk.com/jeffl/antennas/connector-loss/
This was a bench test of a mess of adapters at 2.4GHz and 450MHz. The
numbers worked out to about 0.05dB loss per adapter at 2.4Ghz or
roughly what an equivalent length of LMR-400 would lose. At 450MHz,
the entire string only lost 0.2dB. I've also run the same test in
front of various radio clubs with perhaps 5ft of assorted adapters in
series at 450MHz. (sorry, no photos). The loss was also minimal.

However, I cheated. Not one of the adapters in my test had a "UHF
connector" at either end. When I ran the same test with a string of
UHF connectors, the results were far worse for loss and VSWR at
2.4GHz. For this reason, you're probably justified in replacing the
UHF connectors with N but not because of the added adapters.



--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558