> Using computer software works great for zero beating. But it would be
> nice to have something visual in the radio itself. Although, I am not
> tone deaf - some are. I just prefer the quicker visual spotting.
Even when tone-deaf, you can still zero beat signals. You might
have to "hunt" for the beat a tiny bit more, but it is no problem to
find. Like many skills, a little learning and practice will offset lack of
natural ability to match two tones with hearing them both at the
same time. The "tone-deaf" user simply has to listen for and focus
on the naturally occurring beat between the two tones.
I never ever use the CW TUNE light in my FT1000D, I consider
another one of those unnecessary "features" that blinks away to
make a radio face "look busy".
By far most of the problems with zero-beating relate to the
transmitter not being centered at the same pitch as the receiver.
On CW, if you listen to normal lower pitches (most CW ops I know
actually prefer 400-600Hz tones) there are radios where it is
necessary to order a special low-pitch CW filter and/or offset
passband tuning! You have no way to actually move the carrier
offset in the filters.
Such systems are very poor, but they are probably used because
the radio was designed with SSB in mind where passband tuning
MUST be done with a constant carrier frequency. On SSB,
everyone **wants** the same pitch, they just want a different
passband.
If you carry that system over to CW, the receiver works poorly. You
have to offset filters while the "carrier oscillator frequency" remains
fixed at the design value, which is almost always too high for
serious CW work. (Who the heck ever picked 1000 Hz, when the
middle of the music scale is 440 Hz?)
That should NEVER be done, because it guarantees the TX will be
off from the RX frequency when they share a common oscillator
system.
CW receivers need a carrier oscillator shift to control pitch, not a
passband or filter shift! The beat detection system is a distant
second to proper pitch selection systems.
73, Tom W8JI
W8JI@contesting.com
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