By "freely running" are you implying that they never stop or that their
frequency remains fixed? I assume the ladder. Throwing that capacitance
across the xtal never seemed like a good idea since the frequency is bound
to "slide" a bit. Hey. I like the idea. So we key the buffers and cw
oscillator at the same instant. One buffer and osc gets turned off and the
other turned on with no fsk as before. Sure sounds like a low parts count.
Steve
>
> Well, I suppose I would consider using another buffered crystal oscillator
> ONLY for the CW offset. Then add a buffered stage to the existing circuit.
> Finally, use a damn-fast transistor to switch between the two buffered
> outputs. Here, the two oscillators are freely running and never get shocked
> with the extra capacitance that's now required to produce the offset.
>
Steve Ellington N4LQ
N4LQ@IGLOU.COM
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