Dave, Actually, it's a good idea for all Amateur repeaters in a geographic area to use the same CTCSS tone. With very few exceptions, all 6m, 2m, 220, and 440 repeaters in Santa Barbara County use 131.8 Hz. We don't have interference problems, and it makes it easy for travelers to contact local Hams. Many repeaters with voice ID announce the PL tone as well.
There is a potential problem with more than one repeater at a site sharing the same PL tone, if they are the same make and model. For example, Santa Barbara County had more than a dozen Micor repeaters and base stations at one mountaintop site, and all had 82.5 Hz tones. Even with complicated multicoupler and combiner systems in place, there were instances of interference between them. Once the unrelated systems were given different PL tones, the problems went away. One of the issues with Micor stations is that exciter leakage can occur if all of the shield plates are not reinstalled, with every screw tight. There were also a few instances of leakage from an exciter in one UHF station leaking into an adjacent VHF station, since the UHF station uses a VHF exciter that is then tripled. 73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of WA3GIN Sent: Sunday, August 30, 2009 6:07 AM To: [email protected] Subject: [Repeater-Builder] Nearby Repeaters Looking for opinions. Our club has a couple of 2m repeaters; we chose to run them with PL and we picked 107.2 because that tone freq. was not in use in the area. Recently two other clubs who also have 2m repeaters have decided to utilze the same PL tone freq. Does having numerous repeaters PL'd with the same tone freq. increase the probability of the normally generated intermod/mixed signal to now carry within the produced signal a correct PL tone that may land on the input freq. of another local repeater? Is it considered a bad practice to utilize the same PL for numerous repeaters in the same band all located within a few miles of each other? Thanks, dave wa3gin
