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Old December 2nd 06, 04:42 PM posted to rec.radio.shortwave
[email protected] r2000swler@hotmail.com is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 285
Default AM recption notes.


Michael Black wrote:

I glanced at it and maybe missed something, but DSB is AM. And
he certainly says it at the outset, and when he's talking about the
components he's talking about 2 sidebands and a carrier.

Now, "DSB" often has fallen into the meaning of "DSB with no carrier",
but technically one should specifically define that there is no carrier.

snip
Michael


Back in 1972 when I took my FFC 2nd and 1st class exams DSB was defined
as the sidebands with a supressed carrier. A signal with both sidebands
and the
carrier was simply AM with a BW disgnator. .Now that diffintion may
have slipped
over the years, but from my perspective AM means both sidebands, with a
carier
DSB means both sidebands without the carrier, and ISB means two
different
sidebands with no carrier. I only have received the later, ISB, a very
few times
mainly on ancient STL links.

It might be useful to check out what the ITU says these days about
"AM", both sidebands with carrier", and for this conversation, "DSB"
being both sidebands without the carrier.

Terry