Mu-Tron Bi-Phase Oscillators - why are they so different?

[andy-h-h]

Hello

Just trying to get my head around why the two LFOs in a Mu-Tron Bi-Phase are so different - they both put out square and sine waves.... 

Thoughts / help please?   Why?  Because I'm planning on modding a Phase II to have square and sine wave as options, and I would like to understand more about what is going on in the Bi-Phase.

I could just use the simple one, but that doesn't put my curiosity to bed. 

Andy

[Rob Strand]

If you look at the bottom part of the top circuit you can see a lot of similarity to the bottom circuit.

The differences come in with the diode and the top part of the top circuit.   The top circuit is more
complicated because the rate is voltage controlled.

[andy-h-h]

If you look at the bottom part of the top circuit you can see a lot of similarity to the bottom circuit.

The differences come in with the diode and the top part of the top circuit.   The top circuit is more
complicated because the rate is voltage controlled.

Thanks Rob - I noticed the similarities, but I did not catch on re the voltage control.  I just can't work out why it's like this, if a simpler oscillator does the same thing.  I'm probably missing something really obvious 

[Rob Strand]

.  I'm probably missing something really obvious

The main motivation is the manual control from the external input, the left part of the circuit: Rate control switch set to Pedal.

[andy-h-h]

.  I'm probably missing something really obvious

The main motivation is the manual control from the external input, the left part of the circuit: Rate control switch set to Pedal.

Got it, thank you.  That makes sense.