Remember, I said "sideband bandwidth". A measurement of each sideband and
one will see that it is less than current SSB transmitters. I run a nice
digital filter with a sharp cut-off at 2.4 KHz so my audio response is 40 Hz
to 2.4 KHz. The sideband is then carrier plus 2.4 KHz max. In today's SSB
transmitters with a 2.4 KHz bandwidth filter, the TX BFO is on the slope of
the filter such that the transmitter audio response is 300 Hz to 2.7 KHz
{300 Hz + 2.4 KHz = 2.7KHz} so the SSB signal is equal to carrier frequency
+ 2.7 KHz bandwidth audio so it is wider than my AM sideband by 300 Hz. In
SSB one looses the lower 200 to 300 Hz of the spectrum. Of course there's
not much energy there from the human voice but the upper end is sure
present.
Oh I must admit, I cheated on the wording with malice just to see whom I
could pull out of the woodwork. It worked! Just being a bit picky.
Bob, K4TAX
----- Original Message -----
From: "Martin Ewing" <martin.s.ewing@gmail.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Sunday, April 19, 2009 8:19 PM
Subject: Re: [TenTec] Aux I/O connection
On Sun, Apr 19, 2009 at 3:00 PM, Bob McGraw - K4TAX
<RMcGraw@blomand.net>wrote:
... And oh by the way, my AM transmitter doesn't use any more
sideband bandwidth than current technology SSB rigs and in many cases it
uses less.
73
Bob, K4TAX
I've been around since the AM era, myself, but I don't see how DSB AM
doesn't take at least twice the bandwidth of SSB for the same voice
input.
73 Martin AA6E
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