CGS dual ASM-1 and Modulus LFOs
This CGS dual ASM-1 and Modulus LFO module had a somewhat unusual beginning. I wanted to try building something with surface mount components. The easiest thing I could think of was a basic LFO, so using a number of salvaged surface mount components on a tiny "general purpose" 8-pin chip PCB, I wired up the ASM-1 LFO. Some components may vary in value, but essentially the circuit is unmodified. The PCB is visible stuck to the back of the third pot from the top in the photo to the right.
I thought that while I was at it, I might as well put the Modulus (issue 8) LFO on the panel at the same time, so I made up the panel work so I could finish the module as a Christmas project. Again I used one of my anime style pictures - this seems to becoming a habit! As it turned out, I didn't get to finish the module over the holidays.
Some months later I managed to get hold of some can-type 741s, so for the fun of it, I used these to finish the LFO, adding an extra mark/space ratio control to the output. This makes the LFO somewhat unique in that it already has mark/space ratio controlled by the "symmetry" knob. I can set two different mark space ratios, and mix the outputs to generate micro-sequences. The way I wired the second control, with provision for voltage control, I would have been better off if I had labeled the front panel 0 to 10 instead of -10 to +10.
Readers are permitted to construct these circuits for their own personal use only. Ken Stone retains all rights to his work.
LFO (archived) by Ken Stone, 2000, with permission of the author
- CGS Synth discussion group, for discussion of locating parts, modifications and corrections etc.