Has anyone hooked this up to a scope to check it out?
how does the smoothness knob affect the waveform?
i've been looking for a reasonably sturdy sine wave lfo circuit, with a view to adapting it so that it's switchable from sine/square and maybe sawtooth. Ideally i want to have 4 lfo's of the same frequency in a box, or possibly 2 of one frequency and 2 with double the frequency. With this i'd hope to use to sinc delay tap inputs with tremolo's etc.
First i need to steal a good sine lfo :)
I havn't had experience with the Lune, but if you wnat to make a sine.....
how I do it, is make a triangle, and carefully overdrive half a LM13700 with it. (or, a CA3080, but that is a waste of a 3080 which is harder to get now). Oh look, here's Ray Wilson doing it:
http://www.musicfromouterspace.com/analogsynth/NewAugustSIN_TRI_SQR_LFO.html
Yes, you can do it with a single sided 9v supply if you change bits around & tweak it up, but if the supply changes from 9v, it's going to be not so sinish. More flat on top.
There is also this:
http://mypeoplepc.com/members/scottnoanh/sitebuildercontent/sitebuilderfiles/th_sine_shape.jpg
If you dont want to fudge around with OTA's.
It can be used to create a hypertriangular/parabolic wave form too.
awesome, that ray wilson one is perfect.
would it be possible to add a pot as a volume control to control the amplitude of each output?
i think it'd be good to use a triple pot to control frequency, so the sine/triangle/squares are all sinc'd, the idea was i could use a square wave as a tamp tempo input to a delay, but still use the sine as an lfo for a trem, this way the delay and trem woudl be sinc'd? or even better i could add a switch so to move from independent frequency knobs to a single triple pot.
anyone know where i could get a triple pot?