[sdiy] Tau VCO question

[Simon Brouwer]

lanterma at ece.gatech.edu schreef:
> Thanks to the many folks who responded to our questions about the
> MS-20 VCO!
>
> Another of my students built the Tau VCO (using typical TL08x op amps
> instead of the ones shown).
>
> www.oldcrows.net/~patchell/TAU1010/tau.html
>
> This one oscillates! It gives nice triangle and square waves.
>
> The one curiosity is the voltage swings - the triangle wave is shown
> on yh schematic as going from -5 to 5 volts, but on the scope it goes
> more like -2 volts to a little under 6 volts.

Check if Q5/Q6 are clipping at different positive and negative voltages.
Broken or incorrectly wired?

>  And the square wave is
> like -13 to +14 volts.

See the TL084 data sheet about its output swing.

-- 
Vriendelijke groet,

Simon Brouwer
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