At 2/7/2005 02:30 PM, you wrote: >Hi folks > >Imagine this scenario. 2 quality, UHF repeater colocated at the same site. >Both repeaters are higher power ( > 50) out of duplexers, duplexers are >high quality BP/BR types. Here's the kicker - they're spaced 25 Khz away >from each other but not inverted from each other. > >Now, theory is one thing as to the interference potential without resorting >to mulicouplers and combiners. But what is the real world problem >potential? Anyone want to take a stab at this one?
I've seen more than the expected level of IMD problems for some reason when dealing with close spaced TXs. There is one site around here with 2 repeater outputs 20 kHz apart. When both are up they sometimes 3rd order-mix 20 kHz below the lower output & 20 kHz above the upper output. When present the mixing products are strong enough to be heard 10 miles away. Both systems allegedly have the proper filtering/isolation in place, so I suspect the mix is occuring in a passive (chain link fence, tower joint, etc.), which would explain why it comes & goes. Bob NO6B 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/