On Fri, 2006-10-27 at 17:05 -1000, Ken Brown wrote:
>
>
> >
> > When you go to LCW or UCW, the receiver is offset by the frequency of the
> > "spot" frequency. Some times I have to check into the Badger Weather Net on
> > 3985 on CW even though it is SSB. When I change from LSB to LCW and open
> > the filter, I have to tune down 700 Hz to 3984.3 to copy the SSB. I then
> > turn on the XIT and set it to -700 so they can copy my note. Otherwise I
> > will be on 3985 and not create a tone in their receiver. Try it sometime.
> >
> This feature of modern rigs further confuses the issue. In SSB service,
> the dial (or digital) frequency readout indicates the frequency of a
> carrier that would be zero beat. Signals either side of that will
> produce beat notes of greater than zero frequency. (apparently however
> the guvmint has decided to use the center of the "channel" passband
> instead of the zero beat frequency to designate the frequency of an SSB
> channel, ala 60 meters)
The government has been using center of channel since AM days. That way
they don't have to redefine the channel for different modes, whether AM,
FM, CW, RTTY, or others. Trouble is those users with ham rigs sometimes
miss the fact the assigned frequency is channel center and so end up way
off frequency. Sometimes that happens to the leaders too, made worse by
erroneous calculations of carrier frequency.
<SNIP>
>
--
73, Jerry, K0CQ,
All content copyright Dr. Gerald N. Johnson, electrical engineer
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