Donald Chester k4kyv at charter.net
Thu Oct 31 19:12:41 EDT 2013

From: <manualman at juno.com>

>>" they limit AM to 6 kc" This has been in all three Region band plans for
the last several years. In some countries it has been rolled into their
amateur regulatory laws for years.>>

Canada is one. They did away with mode sub-bands years ago  but imposed a 6
kc/s bandwidth limit. I have never heard of a Canadian AMer getting busted
for "too much bandwidth",  however. I hear Canadians running normal AM rigs
all the time, without any mention of special filtering added to keep the
bandwidth "legal". Some of the VE stations I have talked to say that no-one
pays much attention to that rule. The regulatory authorities pretty much
leave internal amateur radio matters to the hams as  long as they stay
within their allocated frequency bands and don't cause harmful interference
to other services.

I  recall reading on the IARU website a couple of years ago that the IARU
"encourages" local administrations in each country to adopt the provisions
of the band plan into their national regulations. So far the FCC has "just
said no" to specific bandwidth limitations except for the shared channels on
60m, where rules are in place to conform with existing government NTIA

Throughout the decades, starting in the early 50s, bandwidth arguments and
the AM vs SSB controversy have been raging. Some of those years, the
congestion on the phone bands was so severe that during prime operating
hours on a given band it was hard to  find enough of a vacant spot to call
CQ and start a QSO, even on SSB. Those circumstances notwithstanding, the
FCC did not see fit to impose specific bandwidth limits, despite many calls
and formal petitions to the contrary. Now, the lower frequency bands are
much less crowded. During weekend nights on 160 and 80m when the QRN happens
to be  low to non-existent and you would expect everybody and his brother to
be on the air, wide swathes of unused frequencies can usually be found on
both bands these days, and during SSB contests empty spots can still be
found for non-contest operation. This, despite the reportedly record number
of amateur licensees in the FCC data base, something like 700,000. 

If we made it through all those years of extreme congestion without specific
bandwidth limits, why should they be imposed now that the bands are much
less crowded if not downright sparsely populated?

Don k4kyv

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