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blog:2021-05-30:narrowband_proposal [2021/05/31 17:55] – [Narrowband Proposal] va7fiblog:2021-05-30:narrowband_proposal [2021/06/03 18:16] (current) va7fi
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 ===== What About 2m Simplex? ===== ===== What About 2m Simplex? =====
-There's no mention of simplex in the WWARA proposal that I could see.  For a bit of background, in Canada, [[references/simplex |FM simplex frequencies]] are channelized in 15 kHz spread for 2m and 25 kHz spread for 70 cm.((Also note that above 147.420 MHz, half of the channels are for analogue and half are for digital.))  Again, 70 cm isn't an issue because 12.5 kHz fits nicely in 25 kHz.  2m is again more challenging.  Doing the same analysis as before, one possible plan would add new channels, keep on the same frequencies, and change 19 by at most ±5.0 kHz.+There's no mention of simplex in the WWARA proposal, which makes sense since 2m simplex channels aren't congested the way 2m repeater channels are.  However, changing the bandwidth for repeaters does present a bit of an issue for simplex. 
 + 
 +In Canada, [[references/simplex |FM simplex frequencies]] are channelized in 15 kHz spread for 2m and 25 kHz spread for 70 cm.((Also note that above 147.420 MHz, half of the channels are for analogue and half are for digital.))  Again, 70 cm isn't an issue because 12.5 kHz fits nicely in 25 kHz.  2m is again more challenging.  Doing the same analysis as above, one possible plan would add new channels, keep on the same frequencies, and change 21 by at most ±5.0 kHz.
  
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-In itself, there's probably no real benefit in changing to narrowband for simplex, but as I was looking at the menus on my radio, I realized that switching to narrowband for repeaters would mean I would probably change two settings:+In itself, there's probably no real benefit in changing to narrowband for simplex, but as I was looking at the menus on my radio, I realized that switching to narrowband for repeaters would mean that I would probably change two settings:
   - Change FM to FM-N   - Change FM to FM-N
-  - Change my VFO control from 5 kHz to 6.25 kHz +  - Change my VFO control from 5 kHz to 6.25 kHz (or from 5 kHz to 12.5 kHz) 
 + 
 +It would be a bit annoying to keep two different sets of settings (FM-N with 6.25 kHz VFO spacing for repeaters, and regular FM with 5 kHz VFO spacing for simplex). 
 + 
 +The big issue with re-channelizing the simplex frequencies is that, the national calling frequency would move to 146.525.  On a spreasheet, it's possible to pin the calling frequency to 146.520 and change all the other frequencies around it, however on my radio, when I set my VFO spacing to 6.25 kHz or 12.5 kHz, I can only select 146.525, not 146.520.  Many radios are also pre-programmed with a calling frequency button set to 145.520 so that would be a much bigger change.  Maybe this is one of the reasons that WWARA doesn't address simplex frequencies. 
 + 
 +In any case, this proposal seems to be moving ahead albeit very slowly.
  
blog/2021-05-30/narrowband_proposal.1622508933.txt.gz · Last modified: 2021/05/31 17:55 by va7fi