In the early '70s I coordinated a repeater in Texas(146.985) between a 146.97 repeater in Dallas and a 147.70 repeater near Sherman. One was 50 miles and the other about 40 miles away. My coordination required that I not have any complaint from either already established repeater to continue my operation. I operated this repeater for quite a few years before Texas shifted to a 20 kHz spacing plan, when I was assigned a 147.16 frequency. I never had any complaint while using a Spectrum transmitter and receiver which I had assembled on a chassis with a homebrew controller.
I am sure that many of the CA repeaters using this band plan operate without any problems, so it is a workable band plan, proved many times. 73 - Jim W5ZIT --- On Wed, 3/25/09, [email protected] <[email protected]> wrote: From: [email protected] <[email protected]> Subject: Re: [Repeater-Builder] Thank You - Interference Help - WTB To: [email protected] Date: Wednesday, March 25, 2009, 9:54 PM At 3/25/2009 15:35, you wrote: >Back in the day, a channel was 30 kHz wide. When they were split to meet >demand, California was not the only coordination jurisdiction which chose >to put the "half channels" upside down. From what I gather from the >old-timers, it was easier to protect your input from a single, consistent >signal, (the other repeater's output,) 15 kHz off your input but far away, >than it was to deal with an ever-changing pool of users who could be right >under your site, trying to work the distant repeater with high power and >frequency tolerance inferior to the distant repeater. Precisely, Paul. Glad to see others have figured out the reasoning behind our oft-trashed bandplan. The best part is that with a little extra planning & spec'ing, 60 or even 40 mile separation isn't necessarily required to make it work, although you've got to use good equipment - no 30 kHz channel-spec' d radios without modifications. >California had to be first in finding solutions to many band-crowding >issues. Maybe hams there will be the first to narrow-band? Our 4 D-Star pairs are spacing @ 10 kHz; no interference complaints so far. Bob NO6B
