I need the schematic of a very simple sinusoidal signal generator

[jpm83]

What worries me about the screenshot, is that the 'distortion' - which may either be a genuine representation, or else an artifact of the measuring equipment - is different, from one cycle to the next.
That makes me pretty suspicious

This could well explain it, Paul:

Well I played around with this today and 4,7nf C1 & 250k R1 gave me this at 2530,00 Hz

(my highlight).

About 10X (easily) the frequency you'd want, unless that comma is supposed to be full stop?  Would need to see the other resistor values used to do the calculations.

The value of R1 is a value of the pot I'm using not the exact resistance of R1. The frequency that is used here is what gave me "purest" saw wave. When I used lower frequencies The waves looked like "shark fin" and I couldn't fix the with "symmetry pot".

Janne

[gez]

Because you've used a comma , your frequency figure is ambiguous.  From what I understand, some parts of Europe use this instead of a full stop.  Please leave out the comma (and decimal places) for reasons of clarity when quoting figures.  In which case, what is it: 253kHz/250000Hz (keep things rounded for simplicity, please) or 2.5kHz/2500Hz?

If the latter, then I still say reduce your amplitude.

[jpm83]

Because you've used a comma , your frequency figure is ambiguous.  From what I understand, some parts of Europe use this instead of a full stop.  Please leave out the comma (and decimal places) for reasons of clarity when quoting figures.  In which case, what is it: 253kHz/250000Hz (keep things rounded for simplicity, please) or 2.5kHz/2500Hz?

If the latter, then I still say reduce your amplitude.

Sorry about the confusion about that comma thing, I should have known that since I asked from my bank when I ordered some stuff from futurlec which one to use when paying the goods.
    I have played around with the amplitude and it lowers somewhat the THD, but it ranges from 2.5 to 20 THD as I turn the frequency pot. It looks like to me that the symmetry pot has to be adjusted every time I alter the frequency.

Janne