I believe the OP is essentially correct. The "2M sub-band" didn't come until much later - I was thinking it was the late 70s, but it could have been the early 80s.
Your point was why the 146 MHz pairs were more popular - because the techs could not use the 147 MHz pairs. The 146 MHz segment was originally 60 kHz channels (146.610, 146.670, 146.730, Etc.), then went to 30 kHz in most areas - going to 20 kHz channels in some, then the 30 kHz was again broken down into 15 kHz channels. The sub-band was always 20 kHz until some areas changed that, too. Check out some of the older RDs for more info. Some of the early 70s ones even listed the Input/Output modulation, such as 5/5 or 15/5 or 15/15 (meaning deviation in / deviation out). Joe M. wb6dgn wrote: > > "duh-because when repeaters were first authorized for 2M, they were only > allowed from 146 to 148. 144.5-145.5 didn't come into existence until > the 80's." > > Close, but not exactly. When repeaters first came to be used on the ham > bands in the late '50s/early '60s the 2m band from 144 to 148 Mc was only > available to General class licensees and above. Novice (yes, Novice had some > 2m voice privileges at that time) and Technician licensees were only allowed > to operate in the 2m band from 145 to 147 Mc. Therefore if a repeater owner > wanted to make his repeater available to the widest "audience" he had to keep > both input and output within the 145 to 147 range. Interestingly, there was > a repeater in the S. F. Bay area (somewhere down the Peninsula, I believe, > maybe Stanford) that did have it's input and output on 144 and 147+ with the > clearly stated reason that Novices and Techs. were not welcome. Never seemed > to bother anyone I knew; that group carried on some pretty "stuffy" > conversations anyway and there were enough 145 to 147 machines to go around > including at least one AM repeater. However the only repeater at the time > (tha t I > know of) using 600Kc separation was the WB6AAE repeater in the foothills > east of Oakland on Grizzly Peak. If they had a role in establishing the > later standard, I have no idea > Tom DGN > > --- In Repeater-Builder@yahoogroups.com, wd8chl <wd8...@...> wrote: >> Rev. Robert P. Chrysafis wrote: >>> wonder why the fcc does not allow acssb above 30 mhz on the ham bands? >>> seems >>> to me they would want to promote more efficient modes through all the ham >>> bands. >>> >>> another interesting thing would be to see 2 meter repeaters go to 2 or 3 >>> mhz >>> splits and employ some form of efficient modulation mode instead of the >>> same >>> old 10 khz fm. >>> >>> and i am sure we will be all dead before this happens :) >>> >>> one can imagine though. >>> >>> better tx/rx isolation, cleaner signals, employ some form of narrow band >>> modulation scheme and we could even ease congestion on 2 meters. >>> >>> >>> i still can't imagine how the 600 khz split was decided for 2 meters when >>> there is room for at least a 2 mhz split. >>> >> >> duh-because when repeaters were first authorized for 2M, they were only >> allowed from 146 to 148. 144.5-145.5 didn't come into existence until >> the 80's. >> >> No-2M is too populated to do any changes. Not gonna happen until they >> just flat stop making FM gear. Not in my life time, not in your kids >> lifetimes, probably not in your grandkids lifetimes either. >> >> Same with the 150-174 LMR band...WAAAAAY to much gear out there to try >> to standardize input/output. >> >> Look at the bright side-at least the ham band HAS a standard. There is >> none in the LMR segment. >> > > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > > > ------------------------------------------------------------------------ > > > Internal Virus Database is out of date. > Checked by AVG - www.avg.com > Version: 8.5.387 / Virus Database: 270.13.38/2274 - Release Date: 07/31/09 > 05:58:00 >
