On Feb 1, 2010, at 10:56 PM, Gary Smith, KA1J, wrote:
> There were several multipliers I needed to go after
> and I had to transmit off their transmit frequency
> to be heard. Sometimes 50-75 Hz was all that was
> necessary but I could have replied on their transmit
> freq. all night and they would have never heard me.
Most modern transceivers actually do transmit CW on a carrier frequency
precisely locked to the pitch of the local sidetone chosen by the operator.
Unfortunately, many of those same transceivers don't allow their owners to set
the pitch low enough for their personal preference, so some operators (blush,
blush) end up off frequency when replying to another station's CQ because
they're unwittingly tuning for the most pleasing received pitch, which may, as
Gary notes, be 50 Hz or more away from perfect zero-beat. Example: My
Kenwood's lowest selectable pitch is 400 Hz, but I prefer to listen around 300
Hz. If I tune a station in so that the resulting beat note I hear from him is
300 Hz, my transmit frequency will be 100 Hz off from his. The "simple" cure,
of course, is to match the pitch of his signal to your local sidetone pitch,
but in the heat of battle you may forget.
To make sure I don't lose any replies to my CQs because of others with a
similar situation or who have accidentally left their RIT or XIT on, if I'm on
Upper CW ("normal" CW on my Kenwood, Reverse CW on a K3, for instance) I turn
on my RIT and set it at -100 Hertz or thereabouts. If, following a CQ, no one
calls me within this "offset" passband, I sweep the RIT up and down. Every now
and then I catch someone calling me as much as 500 Hz off in one direction or
the other. (My assumption is that this is frequently a person who doesn't
realize his RIT or XIT is "On".)
With modern rigs like the K3 having such excellent dynamic range, my preference
when CQing is to combine 100 Hz of RIT offset with a filter passband of 500 Hz
or so, and to obtain the final selectivity between my ears. Then I can copy
stations calling me who are on either side of my transmit frequency by as much
as 200 Hz or more without having to tune around. The benefits of this approach
are:
a. I seldom require a repeat from losing the first part of someone's
callsign, since almost everyone who calls me is already within the passband of
the receiver.
b. This allows me to keep both hands on the keyboard or use one hand to
select the best RX antenna.
It may take some practice to keep your "internal filter" from jumping from one
signal to another when many stations are calling you. Of course, my internal
filter works best when I'm not exhausted.
Bud, W2RU
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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