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Old November 13th 03, 01:49 PM
me
 
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Default Repeater experts....HELP!

Hi guys. Thanks in advance for any help. Please post
responses in NG as my email 'reply' address is fake
since some don't know how to mind their manners.
I recently put back into service a Hamtronics REP100
two meter repeater with a new Telewave Duplexer and
the antenna is a Ringo Ranger II with radials. Coax to
the antenna is RG8 superfoam and jumpers between
repeater and duplexer are RG8 superfoam.
Here is the problem. I am experiencing 'desense' on
the repeater to the point where it takes a signal of S5
or better to get in. A lesser signal just makes the
repeater "chop" (continually opens and closes the
transmit side. The Duplexer was factory tuned
(for what it was worth) and I did 'tweak' it and got a
much noticible improvement. Before tweaking, it took
an S9 or better to get in. I realize I should be running
(supposedly) double shielded jumpers from repeater to
the Duplexer, but I can't imagine they are going to make
that much difference. I am also told to mount the duplexer
in it's own enclosure (it's rack mount so that would be cute)
to keep it away from the repeater.
The Hamtronics manual says you HAVE to use a
duplexer with at least 95 db of isolation (try to find one)
and mine is 77db. I really can't imagine there is not
enough isolation, because I know where there are other
machines running with old duplexers with much less
than 77db of isolation. Just to add to the mix, I sent
the repeater up to Hamtronics and had it tuned and
checked out and it is 100 percent, so I *suspect* it
is not a repeater problem. (Someone suggested to
try killing some of the sensitivity of the reciever).
So....looking for ideas and suggestions on what to try
next (other than double shielded jumpers to the duplexer).
Thanks for any help or ideas...
73's Rick