Simple, Jim...
When there is sufficient low frequency energy (and I mean below 100 Hz), an AM
detector can use it to demod the SSB signal! It will sound slightly off
frequency because the energy isn't exactly where the carrier is supposed to be,
of course. Try tuning off his freq a little and you'll hear the energy up in
freq a bit, but it's clearly the voice and not a constant carrier. I've never
seen an eSSB'er with carrier leakage like what some claim, but I'm not foolish
enough to claim they don't exist. I happen to enjoy full fidelity SSB, and it
uses MUCH less BW than its AM counterpart, which I use hardly at all anymore.
I used to be an AM'er because of the better quality, but now I get that (or
better in a lot of cases) using eSSB. My TX -6dB BW is <4.2k and -26dB BW is
under 5k, both referenced to 1 kHz levels, with my voice, peak held on an
HP8563E spectrum analyzer. I have *NOT* modified my transmit whatsoever, other
than to feed my audio to it -- it does what it does
out of the factory box, but I have modified my RX for a flat response and
accurate monitoring.
I will *NOT* get into a debate over IMDx and the pluses & minuses of eSSB here.
It's way off topic (by a long shot) and I've been down that road a number of
times elsewhere (with a few that subscribe here). There are incompetent
operators using all modes, eSSB included. Email me off list if you'd like more
info...
Good Luck & 73,
Joe, N3JI
----- Original Message ----
From: Jan Erik Holm <sm2ekm@telia.com>
Cc: Amps@contesting.com
Sent: Thursday, June 29, 2006 6:57:50 AM
Subject: Re: [Amps] HLA-150 information page
Yes, IÂve read this before but itÂs very very true
and itÂs getting worse almost by the day.
IÂm sorry to say but I do think itÂs a lost battle.
By the way, from what you describe the picture is
even worse in Europe.
Even radioÂs that are "decent" from the start we have
people getting into and doing this or that to get
them wider and then they think they sound nicer.
Forexample, right now in Sweden we have a fellow
on 80 playing that game. He is over 15 kHz wide
and very strange sounding, his SSB is perfect copy
in the AM mode on my RX, beats me whats going on.
I just do not understand some people anymore.
73 Jim SM2EKM
--------------
Tom W8JI wrote:
>> By the way, the SD1446 seems to be a 60W transistor,
>> 200+ Watts out from two of those, jeez! No wounder
>> some people are splattering.
>
>
> I did a check on some bands a few months ago and results were terrible.
>
> See:
> http://www.w8ji.com/rm-11306.htm
>
> I think it is becoming a worry. Anything being sold or promoted should
> be tested for IM before being released..
>
> 73 Tom
>
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