[AMRadio] 7160 tonight: Suggestion

Jim Wilhite w5jo at brightok.net
Thu Apr 2 19:15:33 EDT 2009

These are the arguments I remember from the mid 50s about why we 
needed to restrict bandwidth of  our transmitted signals.  Also the 
fact that there were so many more hams that were on the air. 
Collins lead the way with the 75A1A which, with modifications would 
have, what, 2.4 Kc bandwidth?  Other manufacturers followed suit. 
Most receivers and transceivers have 2.4-2.7 Kc bandwidth at the 
most.  So the outcome was the ARRL supported SSB to double the 
number of stations that could transmit at the same time.  Today 
people are decrying the fact that there are fewer hams than in past 
years.  That should give us more space.

Today we modify our rigs to utilize from 100 or so cycles out to 
8-10 Kc so we sound better.  Even the SSB crowd is doing it out to 
about 5 or 6 Kc.  I'm sorry my WRL VFO is not stable enough to stay 
on one frequency for an extended period.  It does wander at least 
100-500 cycles between transmit and receive.

So if someone using a modern transceiver wants to move about 1.5 Kc 
near me, they better have an auto notch function or be prepared to 
change the notch knob as my VFO wanders.  Last I read part 97 there 
are no standards for frequency stability on the ham bands.

I do try to be considerate, I just wish the SSB crowd, especially 
the contest and DX bunch would try.


>I see this all over, and its just poor operating practice.
> Some guys will be 2 or even 3 KHz low, someone else might be 1 or 
> 2 KHz
> high, some guys are overmodulating and/or have no restrictions on 
> the high
> end of the audio, and the qso is 10 KHz wide, which is rude.
> Not so important on an empty band, but still poor operating 
> practice all
> around.
> I know its hard to keep some rigs on frequency, you need to zero 
> beat often.
> When I had the drake R4C, sometimes I only heard one guy in a qso, 
> the other
> guy was out of the passband!

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