[TenTec] Sidetone revisited

[Tom Rauch]

> I had an MFJ DSP unit and sorry I ever sold it. Yes it does clean up
> those sidetones but so will any sharp audio filter, even non DSP such
> as the famous Autek QF1. The MFJ DSP seems to be the only one with no
> discernable delay which almost makes me wonder if it's really DSP when
> operating in the CW peaking filter mode. 

I added bypass to the 784 DSP for transmit so you don't have to 
filter the sidetone, but of course you don't have to use the bypass 
feature on the amplifier/radio keying line. It is a real DSP system, 
and it does have a few milliseconds of delay. It is generally not 
bothersome when you listen to sidetones through it, unless you go 
really fast!

Another choice is a op-amp filter, easy to build and add to most 
radios. I used them in my old T4XC's even.

I don't know why radios and keyers use such crappy sidetone signals. 
Ease of building the oscillator?73, Tom W8JI
W8JI@contesting.com