No, that has not been done. He did try a different Kenwood repeater - no help. He brought his duplexer to another site - no desense. He tried a different duplexer at his site - desense.
The intermod with the cell system is a strong candidate. His antenna is on top of the platform that the cell antennas are mounted around the perimeter. The entire repeater is in a 5ft tall Motorola cabinet and probably weighs 100 pounds. Moving it would be possible but not easy. The problem is: after he moves it and has no desense, how does he fix the situation at his current site? Thanks for the suggestion, however. I'm passing all info on to the trustee. Bob M. ====== --- Mathew Quaife <[EMAIL PROTECTED]> wrote: > Bob, just a suggestion, has he taken the repeater > away from the site, hooked it to another antenna to > see if he might be riding along a frequency there at > the tower site. He could be pulling something in > from a second harmonic there. The only reason I > mention this, is a friend of mine had a 440 repeater > at a cell site and had something similiar happen. > He took it to another antenna, and the problem was > gone. I know he ended up installing a circulator, > but I also think the cell site ended up installing a > peice of equipment, but not sure what they put in. > That was about three years ago, and the whole entire > crew is gone, so not sure if I could find out what > they installed. > > Mathew > > > "Bob M." <[EMAIL PROTECTED]> wrote: > Hi. A local UHF repeater is having massive desense > problems. Everything is clean with a dummy load > attached to the duplexer, so we know it's a problem > with the connectors, coax, antenna, or jumper > between > the two. This is a two-month-old system at a > cellphone > site; nothing else there. The repeater is the only > thing on 444.5 MHz. > > I'd like to try a circulator before buying one, > since > if it doesn't help the situation, it's a waste of > money to have it there. I would agree however that > its > presence would be mandatory if this was a busy site, > but for now it's just his repeater and all the > cellphone equipment. > > He's running 200 watts out of a Henry amp, through a > TxRx 4-section duplexer. We see a 20dB rise in the > noise level at the Rx port when the transmitter > comes > on, with the system connected to the coax/antenna. > Absolutely no change with a good dummy load attached > to the duplexer's output. We even have desense with > the 20 watts out of the exciter (power amp > bypassed). > The antenna is a super stationmaster cut for the > 440-450 band. The coax is 7/8 and there's about 150 > ft > of it. > > So if someone has a circulator and reject load that > would be rated for 200 watts to pass through it, > please contact me. If there's a way we could try it, > and buy it if it helps the situation, that would be > ideal. > > Thanks. > Bob M. > > > > __________________________________ > Yahoo! FareChase: Search multiple travel sites in > one click. > http://farechase.yahoo.com > > > > > > Yahoo! Groups Links > > > > > > > > > > > --------------------------------- > Yahoo! FareChase - Search multiple travel sites in > one click. __________________________________ Yahoo! Mail - PC Magazine Editors' Choice 2005 http://mail.yahoo.com Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
