Adding a sub oscillator to the Teisco 60F

[wahee]

hi

I have successfully made a very simple 4024 based sub oscillator and have tested it on a scope and it does indeed put out division of the inputted square wave.

I wanted to add this to my 60f. I have successfully located the square wave output and the 4024 outputs a divided signal.

I have been having issues trying to inject the signal into the synth, and also how to mix it with the existing signal. After killing one 4024 I though it was better to stop and really get this right.

Attached is the schematic for the 110 model, 2 oscillator big brother of the 60f. I thought if I could inject at the filter it may be the right thing.

Just wondering if anyone more knowledgeable than me would have any insights

many thanks

60f.JPG

[guest]

replicate the circuits in the mixer section. add a resistor from the 4024 output to the top of a 50k or 10k pot, and then take a 100k from the wiper of that put into the mixer.

[wahee]

replicate the circuits in the mixer section. add a resistor from the 4024 output to the top of a 50k or 10k pot, and then take a 100k from the wiper of that put into the mixer.

hi managed to get it sorted. Did as you said.
I had to use quite a high value pot 500k. Then a 100k in and 47k out. Gave satisfactory levels.
The pot had an integrated switch so I can turn off the sub if required, sounds great

Quick vid:

[guest]

sounds great!

[wahee]

sounds great!

cheers, it's actually a decent mod to do