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Old March 11th 08, 07:17 PM posted to rec.radio.amateur.antenna
John Passaneau John Passaneau is offline
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First recorded activity by RadioBanter: Jan 2007
Posts: 58
Default Attenuation Questions

Ian Jackson wrote in
news
In message , Jeff
writes
I'm surprised at these reports, but not too much except for the 2 dB
connector. It must have had some internal corrosion, or perhaps
something like a helical internal contact causing an impedance
mismatch that would look like loss in a matched measurement system.
(Some el crappo UHF barrel adapters have found to be constructed
that way.) I've seen some awfully shoddy BNC connectors at ham
conventions and wouldn't use them for anything at all critical. But
the OP asked if there was a place he could find the losses of
various kinds of connectors. I don't believe there's any place you
can go to find the losses of shoddily made or improperly assembled
connectors or adapters. Decently made and properly assembled
connectors of standard types show no appreciable loss at 1 GHz. If
loss is a concern, my advice is to buy name brand connectors, and
especially avoid the cheap stuff you see at places like flea
markets.

Roy Lewallen, W7EL

snip
I have to admit that I've routinely worked to 870MHz, and recently
even to 1003MHz, but rarely ventured higher. However, I've never found
any excessive loss in a connector which could not be accounted for by
a straightforward 'bad connection', ie usually a total or partial open
or short circuit, whether in the making off of the cable, or in the
construction of the connector itself. Honest!



One thing, SMA connectors are rated for 500 connection cycles, I don’t know
what happens after that, but on test equipment 500 connections might happen
fairly fast. I know from experience that SMA is a connector that’s easy to
put on badly.

John Passaneau