Have you swept the Antenna and Transmission Line with a Site analyzer or a Comms Analyzer / RF Bridge?
Peter On Tue, Aug 10, 2010 at 8:35 AM, <radi...@aol.com> wrote: > > > I don't think there are any drain plugs on this antenna. connection seals > were checked and re-done. I am not familiar with the desense tests, but > both repeater and duplexer were replaced. New duplexer tested at more than > 100 db isolation and power is about 75 watts .Problem must be with hard line > (replaced already), tower or antenna. > > In a message dated 8/10/2010 12:09:39 A.M. Eastern Daylight Time, > petedcur...@gmail.com writes: > > > > Hi, > > Juts a thought: > > Sometimes certain antennas have a drain plug at the bottom and sometime one > at the top. You should remove the drain plug at the bottom for normal > mounting or the one at the top for inverted mounting. If you don't water > can ingress, then can't escape and build up. Another thing to check is > the connector sealing. > > Peter > > On Mon, Aug 9, 2010 at 4:49 PM, Kevin Custer <kug...@kuggie.com> wrote: > >> >> >> radi...@aol.com wrote: >> >> Hi Kevin, >> The desense is a staticy reception of "weaker" signals( ie an HT at 25 >> miles) It had gotten worse as it started to affect strong signals too. If >> the transmitter was turned off, the repeater could hear just fine. Problem >> is intermittent and often followed a rainy day. We replaced "EVERYTHING" A >> UHF repeater on the same tower is unaffected. At this point we think the >> "new" antenna is failing. Tower sections have been bonded grounds improved >> etc etc >> >> >> To know whether or not the problem is the antenna system, do a >> desensitization test directly at the antenna port of the duplexer using a >> good load and a lossy tee or other acceptable method like a coupler slug >> installed into the Bird Watt meter. If you don't know how to perform a >> desense test, there are several articles on the website that will assist >> you. >> >> If this proves good, then you have more work to do on the outside. >> >> Let us know... >> >> Kevin >> >> > >
