On Wed, 20 Feb 2002, Jinx wrote:

> > btw, Jo, is not the middle of the night or early in the
> > morning in NZ ?
>
> Dunno, haven't looked outside lately
>
> 10:05pm actually. Just spent 15 minutes rummaging around
> in Philips new data sheet site
>
> http://www.philipslogic.com/datasheets/
>
> I've got an oscillator circuit that I used for a guitar tremolo. It
> took some playing around with to get it very slow, I'll dig it
> out later. It used a couple 0.47uF capacitors and a 741 which
> drives an MC3340 voltage controlled amp. The problem I found
> with those low frequency ones using op amps and capacitors
> is that the sine wave wasn't always very symmetrical. Even a
> chip like the 8038 has a lumpy sine wave at LF

  maybe there are two distinct problem:
1. the offset of the OA is not compensated
2. the output is AC coupled through a capacitor and there is no
resistive load to ground behind this capacitor. The effect is a variable
DC component passing by through the capacitor untill full charge.

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