LM13600 audio osc

Scott Gravenhorst chordman at flash.net
Tue Mar 31 19:15:51 CEST 1998

Wow Paul, I had a similar problem with it range wise.  I assume you
built the osc in the appnotes for the LM13600.  I used a different
method to get full range.  Actually, I just copied PAiA's FatMan V/I
converter design and bingo.  Unfortunately, I can't speak to the
asymmetry issue, since the cap I used was to set the oscillator range
rather high and I use only the square output because it is intended as
a clock for a noise generator (shift reg) and a complex waveform
generator.  These drawings are on hyperreal.  The oscillator tracks my
FatMan very well.

On Wed, 1 Apr 1998 00:35:43 +1000 (EST), Paul Perry
<pfperry at melbpc.org.au> wrote:

>Well at last I have some good news....
>I have been wondering why I can never get a wide range audio osc
>going with the LM13600, well I put a foward biased diode in series
>with a 10k resistor going from the wiper of a pot across the rails
>to the bias input... now I have 1 Hz to 20KHz exactly what I wanted..
>oh, also a 330 ohm resistor at one end of the pot to stop the thing
>locking off at the low end.
>Now if someone can tell me why at the very low end the triangle goes 
>a very happy paul perry melbourne australia

-- Scott Gravenhorst

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