Re: [HARC] 2 meter Simplex Frequencies
- View Source--- In email@example.com, Ernest Lloyd <w8el@...> wrote:
>operate 2 meter FM until the middle 1970's. I think it was in the 80's
> Actually, Chuck could give better info for this region. I did not
that the old 30 KHZ spacing was changed to 20 in some places and 15 in
others. The older commercial equipment was not designed for the
narrower channel width, which made a lot of obsolete wide channel
commercial equipment available cheaply to amateurs. I don't remember
the year that the newer narrower (15 KHZ?) equipment was mandated for
commercial VHF service. Laren lived through that era also, so he
could fill us in on more history. How about it, Chuck and Laren?
> 73, Ernie, W8ELHmmm.... Well, I don't know when the commercial people went to 15kc
> "John Wehmer (WB9JSR)" <wb9jsr@...> wrote:
spacing. And the spacing depends on which band you are talking about.
VHF (commercial) went the 60/30/15kc route and now they are splitting
again, for more channels. I'm not sure how UHF went. It was spaced
for many years at 25kc with 12.5kc used for lower power operations. I
think they are also splitting that again, too.
The 2M band slso started with the 60/30/15kc route as more channels
were needed and technology improved. Michigan went from 30 to 20kc
spacing for repeaters between 146 and 148mc I think in the early 80s.
The coordinators in office at that time saw a way to fit existing
repeaters more easily into the band, while also, sort of, existing
with other states and Canada. It doesn't always work so well. For
instance, 147.160 is just 5kc away from other states' 147.165 channel.
There are a bunch of other similar spacings as the 20 vs 15kc
channels go in and out of sync. We're lucky here in Holland bacause
7.06 is 15kc away from the nearest channel. So we don't hear someone
5kc off frequency, which usually sounds horrible. (Skip can be
annoying; distorted skip is downright awful.) Although with CTCSS in
place and operating on your radio, it's not so much a problem anymore.
Don't know if that ramble answered your questions....