Yes, better, but still a lot missing.
At least, see page 76 there for a complete DFG schematic, and pages 79 &
80 for a complete A3 (order is srdawkcab).
HF problems aside, fix the triangle FIRST and make it as perfect as
possible.
The HF circuit is the *cause* of the triangle problems. The triangle is
just a constant current into a cap. When it reaches +5 volts the detect
circuit switches the current source to ramp down to -5 volts, then the
cycle repeats. The HF circuit modifies the threshold of the +-5 volt
detect circuit which is part of forming the triangle wave. The problem
is the -5 volt detect is happening too soon and the triangle is not
going far enough negative. The *only* happens when switched to the 10k
or 100k ranges. The only difference in the ranges is that the HF circuit
is kicked in (and the value of the integrating cap, but they are
different between the 10k and 100k ranges).
Just to be clear, the triangle still looks just like a triangle. The
symptoms are:
1) doesn't go negative enough,
2) faster than it should be,
3) frequency is erratic,
4) sine wave is truncated on the negative half
To me, this clearly points to the HF circuit. The wave shaper only
affects the sine wave and won't change the frequency. The sine wave is
affected because the triangle doesn't go negative enough.
Well, then work on the negative threshold sense circuit as well as
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