I have a function generator based on the venerable (=crap and no longer available) 8038. The square and triangle waves seem pretty clean, but the sine has a funny glitch that appears as the frequency increases. Here it is circa 1KHz:
Would I be way off the mark thinking that decoupling capacitor(s) near the chip might fix the problem? If so, given that the chip uses +/-15V would 2 caps, one from Vcc to ground and one from Vee to ground be needed? It's a ready made PCB so I'm going to have to bodge something up on the solder side.
If I'm wrong, what might be the cause?
 Courtesy of my shiny new
DS1102. Winking smiley.