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[email protected] · December 3rd 06, 02:48 AM posted to rec.radio.shortwave

wrote:
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.

No arguments from me. That was how I was taught in college, though ISB
was never a topic.

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