[Elecraft] K3: Voice pitch adjustment on SSB

[Dale Boresz]

Hello Oliver,

Actually, the wider the bandwidth and the higher the quality of the 
audio, the easier it is to tune accurately. Precise tuning of a 2.6KHz 
signal is much more difficult than with a 3.6 KHz signal - where it is 
pretty easy to achieve an accuracy of about 5Hz to 10Hz if your receiver 
bandwidth can match or exceed the transmit bandwidth -- whether you're 
familiar with the voice of the other operator or not. All ears are not 
created equal though, so YMMV.

This is not a plug for ESSB, merely an observation. Besides... I'm a CW 
op  :-)

73, Dale
WA8SRA





O. Johns wrote:
> Folks,
>
> I read the web pages about ESSB, after seeing on the reflector that 
> the K3 now supports it.  It struck me that even ESSB doesn't solve one 
> big issue with voice transmission: PITCH.  Tuning the SSB receiver 
> changes the overall pitch of the received voice.  Unless you have met 
> the sending ham or at least talked to him/her on the phone (or on 
> AM!!), you have no real idea how high- or low-pitched the voice really 
> is.  One can only guess, and get a sort of feel for what a reasonable 
> tuning is.
>
> One way to solve this may seem a joke, but it isn't.  Everyone should 
> buy a little 440 Hz pitch pipe, the kind used to tune musical 
> instruments.  Then, say, the net control could blow his pitch pipe at 
> the start of the net and all the listeners could blow their little 
> pitch pipes while listening to net control.  They would all then 
> adjust their receiver tunings until the pitches matched.  Like a 
> shortwave orchestra tuning up.  (Of course, this might violate the FCC 
> rule against music on ham radio, but maybe not if the pitch pipe was 
> near a pure sine wave.  Then the signal transmitted by net control 
> would be just an ordinary CW signal, but at 440 Hz from the net 
> control's suppressed carrier.)
>
> A refinement would be to build a pure 440 Hz tone generator into the 
> microphone preamps of radios.  Net control pushes a button while 
> transmitting and it goes out over the air.  The net members push 
> another button while receiving to produce a 440 Hz tone in their 
> speakers along with the received signal from net control.  Then the 
> receiving operators adjust their receiver tuning until the pitches 
> coincide.  For the tone challenged among us, the receiver tuning could 
> even be automated, much like the K3 already does for sidetone on CW.
>
> This scheme came to me when I was adjusting the audio parameters on my 
> K2.  I had the K2 running into a dummy load, and was listening to it 
> on headphones plugged into a TenTec RX320D across the room.  Since the 
> K2 was on a dummy load, I tried whistling and was surprised and 
> pleased to find that the PITCH of my whistle didn't match the one I 
> was hearing on the phones.  But I could adjust the RX320D tuning until 
> they did match.  Guarantee of zero beat and realistic pitch in voice 
> reception.
>
> Doesn't seem that this would be too hard to do.  Maybe the K3 could 
> even do it in firmware?
>
>
> 73,
>
> Oliver Johns W6ODJ
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