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Subject: RE: [PolySix] Square Wave on the MG (LFO) Instead of Triangle?

From: "backshall1" <backshall1@bellsouth.net>
Date: 2013-08-22

There's definitely a square wave there already on the LFO. I can't remember
exactly where, but I know I've seen it on the scope. I've got too many other
projects in pieces on the bench right now to pull out a Polysix and open it
up, sorry.

Don B.



_____

From: PolySix@yahoogroups.com [mailto:PolySix@yahoogroups.com] On Behalf Of
chipaudette
Sent: Wednesday, August 21, 2013 9:09 PM
To: PolySix@yahoogroups.com
Subject: [PolySix] Square Wave on the MG (LFO) Instead of Triangle?






Hi All,

I'm looking to mod my Polysix to get other waveforms for the MG (LFO). Right
now, as you all know, the MG has a triangle waveform. I'd really like a
square wave. I'd also like a ramp, but I think that a square wave ought to
be a lot easier.

I looked at the schematic for the MG Oscillator section of KLM-367 but
didn't see anything obvious where I could turn the triangle into a square.
I'm not a master of understanding how these oscillators work, though, so I'm
hoping that others might have some ideas.

My only idea was to insert an op-amp somewhere after Q1. I'd set the opamp
with no feedback, so it would simply rail positive or rail negative as the
current triangle waveform swings through zero.

I'm really hoping to not have to add an active component because it is so
much easier simply to add a switch that shorts something, or adds a cap, or
something like that.

Does anyone have any ideas?

Chip





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