Made two yusynth VCOs the other day.. None works... But the real problem is that at the schematics it mentions using a 1% silver mica capacitor. I have used plain ceramic and multilayer. Voltages are OK. The comparator and OP Amps get nice voltages. No electrolytic capacitors are the other way around. So it has to be this. While I wait for the silver micas, I might put together a yusynth moog filter clone.