Date: Tue, 7 Nov 2017 15:14:43 -0500
From: Larry <pacer99@aol.com>
To: jim@audiosystemsgroup.com, amps@contesting.com
Subject: Re: [Amps] Alpha 87 (not 87A)
<jim,
<i just finished the CQ WW SSB and except for a very few stations the quality
of signals was good. i am using an Icom IC-7800.
<i believe that if each of us take the time to contact the offending station
and explain, in a polite manner that they were "spattering". try to help them
correct the problem. the bands would clean up rapidly. every time that i do it
the problem is solved and the <offending station is grateful. no one wants to
be rude to others. it's a friendly hobby after all.
<complaining does no good.
<73,
<larry
<n7dd
## For folks trying to measure the total BW of an SSB signal, remember not to
inadvertantly add the width of your RX filter...to the other fellows TX bw.
IE: say you are using a 3 khw wide RX filter..and are on 3800 LSB. You will
hear
everything from 3800...down to 3797. Meanwhile the offending station is on
3797 LSB. Assume he is also TXing with a 3 khz filter. On paper, he should be
occupying 3797...down to 3794. You tune across his signal, and you can hear
him from 3794....all the way up to 3800. You tell the fellow that you can
hear him.. 3 down...and 3 up from his TX freq of 3797. No the fellow is not 6
khz wide, he is only 3 khz wide. You have added your 3 khz wide RX BW to
his
3 khz TX BW to arrive at the 6 khz figure.... which is incorrect. That
mistake is done all the time. A better method would be to tune across his
ssb signal, using a pair of 500 hz cw filters..... sorta like poor mans
spectrum analyzer. In actual
practise, it works good. Then you will hear that he is only 3 khz wide.
## I wouldnt put any stock in the Icom fish finders either. They will easily
show a dead cxr as being 2 khz wide, and other erroneous stuff. Also make
sure your NB is OFF, and dont have excess RF gain applied. Shut the RF rx
pre-amp off, NB
off, and back down on the RFor IF gain control a bit..and also switch in some
RX padding, like 6 or 12 db. Then use a pair of 500 hz filters if using a
xcvr that has switchable RX CW filters, or the dsp eq.... then carefully tune
across his signal,
using your MAIN RX. Meanwhile you can simultaneously listen on 3797 LSB...
on your SUB RX. Then you can correlate asap, any splatter products, while
listening on your Main RX..with a pair of 500 hz cw filters in left ear...
while listening to him on LSB... on your right ear....using the sub RX.
Jim VE7RF
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