Low-distortion Audio-range Oscillator

problem with my oscillator

there seems to be a parasitic with my oscillator. I tried to operate from batteries and with a 680 ohm load.
There is a picture in attachement, hope it will render correctly.
Any Idea what causes this?
 

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Isnt that osc spec'ed as 0.1%
No, I asked Victor for one of his oscillators and requested that he measure them, I requested the best one. Some time later he replied that this was the best one he's measured at the -160dB. So that is the one I bought. He didn't think he'd be able to make another that low again as he boards were going to be different and something about the parts, but I can't recall exactly.

I have victors since I first found him on eBay.... doesn't measure that low.
What does yours measure? Did you specifically ask that you wanted the lowest -dB figure that he could make? I had to wait and he had to tweak it, with parts etc., What ever he did, to get it down to that level. I think I had to pay a little bit extra for it, it was a while ago.

Where do you get those distortion numbers?

I got the HP339A distortion number from you. I think you posted the pic and said it was greater than -120dB. Then looking at the image you posted it appeared to be between -123dB and -125dB.

I used the lowest (higher distortion) number that seemed reasonable.

When demian was here, he had mentioned what he does to these boards, I think adding a reg to the V+, V- imputs and changing out resistors along with other changes.

But I didn't want to fool with it then as I had the HP339A water boarding issues. Currently everything is apart and sitting in the music room I'm stuck without a bench or equipment at the moment. Kinda like Demian after the move. Except my move is within...maybe that is worse.

Cheers,
 
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Frex has PCBs for an LT AN67 oscillator, that does a reasonable job at 10KHz. EOSC10Kv3 - LT AN67 10kHz oscillator : new updated version !

This far my own version of the AN67 oscillator, with switchable frequency &c, doesn't work properly at all - I'm unable to get the loop gain low enough for it to stop hitting rails, so I've gotta do some tweaking - alas I keep finding other toys to play with.