AW: Re[2]: VCOs as modulation sources

[Haible_Juergen#Tel2743]

     I really don't know why they chose 560K at the time... to be honest I
     still haven't had the chance to do much linear FM testing. If what you
     say is true I'm sure I'd be pissed off at the wimpy mod depth.

Linear FM stops to be linear when the modulating current exceeds
the reference current: You'll reach zero Hertz on the negative wave.
What you'd want to do is either adding Thru-Zero-FM (requires
a few more components in a triangle VCO, but is nearly impossible (?)
in a sawtooth VCO ), or don't care for linearity/constant pitch and
just decrease this resistor.

     Also I really can't say if dropping the linear FM input resistors to
     say 100K or 47K can potentially hurt the expo converter's transistor
     pair - anybody know the currents involved here? Joachim???

47k shouldn't hurt anything - don't know if something locks up in
a certain VCO circuit. Just try it - can't hurt!

JH.