Not sure about the paging systems.
The repeaters themselves are a variety of systems and their architecture really doesn't matter since the interference can be heard on the input frequency with a string and a tin can. That being said, I know that 2 of them (mine) are using DB-224s, 7/8" hardline and WACOM cans. Mike WM4B From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Oz-in-DFW Sent: Saturday, April 24, 2010 5:17 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Pager Interference Revisited Mike, I'm coming to this late, but I have comments and questions. What type of hardware are the paging transmitters? What are the repeaters in question, and what type of duplexers, feedline, and antennas are used? On 4/24/2010 3:42 PM, Mike Besemer (WM4B) wrote: Not sure what you mean by 'come and go'. It's there when the pager transmitter is up, gone when it's not. In another message you implied it sweeps across multiple repeater inputs. It also comes and goes with heat and sun. we may have days with no interference if it's cool and cloudy or just plain cold. Rain makes no difference. We saw the same thing with Radio Shack and Winegard active TV antennas on RVs. The problem was a high band pager and our UHF radio inputs. Nothing remarkable about the audio. sounds like clean, clear paging tones. Never heard anything else. This implies a first order contribution to a mix or spur. If the second or third harmonic of the pager was involved, the deviation would be a suitable multiple and should sound distorted. Might be good to ask him what transmit dev. he runs, or measure it. There is an abundance of TV stations, DTV, translators, AM, FM. you name it. Yeah but this sounds like something flying. If mixes sweep across your input one contributor is almost always an amplifier that is oscillating. The two frequencies you mention would require a channel 37 station and those don't exist in the US. The paging signals are both, depending on which site it's coming from. Eh? what do you mean here? I can get my hands on pretty much anything I need. Spectrum analyzer is no problem. I have a good 'connection'. Did some hunting with a spectrum analyzer last year to no avail, but now that I have the ability to call the system and have it send out a page we have a little better advantage. Is the paging system key down, or is it transmit on demand? Can you hear the interference far from your site (several miles?) The ability to DF it sort of implies this. I'd call the area 'populated', but not 'urban'. Mostly housing around the site, but plenty of industry (and towers) visible from the top of the water tank. (We are, by the way, the only user on the tank.) What kind of sites are the paging transmitters on? Rental tower, water tank, building? -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport)
