Thru zero FM schematic is up!

[mbartkow at ET.PUT.Poznan.PL]

Rene Schmitz <uzs159 at uni-bonn.de> wrote:

> I've uploaded the circuit diagramms for my thru zero VCO to:
> http://www.uni-bonn.de/~uzs159/vco6.html
> (to go there from the main entrance see end of this message)
> I've also put up some nice .mp3 examples.
> 
> Comments welcome.


René,

Thanks for very nice schematics. I wonder what is the cause of
the distortions observed when changing the modulation depth.
I suggest some shots from the oscilloscope would be very informative.

Anyway, there is one thing I would personally change in your circuit:
I would reconnect IC2d (as a follower) directly to the output of IC2a,
instead of cascading two inverters. I suspect that in the current 
configuration there is a nonsymmetrical delay introduced by IC2c or
IC2c+IC2d, depending on the polarity of the mod. linear input.

BTW, what are your motivations of using BA6110 instead of CA3080 ?

MB


--

Maciej Bartkowiak, PhD
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