Oh crap.. The "rusty bolt" problem.. Are the DB antennas pretty old?
James Delancy wrote: > > > Let me start by saying that I do this kind of thing all day long for a > living. I have seen it occasionally on some commercial systems with the > same antennas. I have all TX/RX 6 cavity duplexers, and the repeaters > are Motorola (CDR or R1225 type) with circulators and line matchers if > needed. I spent a few hours at the problem site the other night and no > matter how I was trouble shooting it, it pointed to the antenna system > (beyond my polyphaser lightning protection at the ground window/entry). > This is definitely an external mix (IM) that includes my transmit > signal. The mix is strong enough that I can see it on my service > monitor inside the concrete building. No problems at all with a dummy > load, and cutting my power output to exciter only reduces but does not > eliminate the problem. > > hope that all makes sense .. > > James > > Jay Urish wrote: > > > > It's not an antenna problem.. What duplexers are you using?? Repeaters? > > > > James Delancy wrote: > > > > > > > > > Just a quick question for the group. I have two repeater sites with > > > DB224-E antennas on them (ham/gov't split). One repeater site tends to > > > feed back upon itself often (duplexers, radios, cabling inside all ok > > > into dummy load, antenna SWR good). The other repeater site does this > > > occasionally. Has anyone had any experience with this problem with > > > these antennas ... and what is the fix (other than replacement). > > > Station Masters do sound like a good but expensive option though. > > > > > > Thanks! > > > > > > James > > > > > > > > > > -- > > Jay Urish W5GM ex. KB5VPS > > > > ARRL Life Member Denton County ARRL VEC > > N5ERS VP/Trustee > > > > Monitoring 444.850 PL-88.5 146.92 PL-110.9 > > > > > > -- Jay Urish W5GM ex. KB5VPS ARRL Life Member Denton County ARRL VEC N5ERS VP/Trustee Monitoring 444.850 PL-88.5 146.92 PL-110.9
