[sdiy] fun with KBD2e

[Schierl, Dan]

hi list--
has anybody had any experience with TomG's keyboard converter, the kbd2e? I recently put one of these together, and am getting some strange results. 
 
documentation is here:
http://www.ele4music.com/pdfs/kbd2e.pdf
 
I noticed 4 or 5 discrepancies between the schematic and the pcb, and i believe I have corrected these. also, i noticed 2 discrepancies between the parts list and the schematic, and I think I got those right as well. the pitch CV out seems to be working fine, but the Gate out is acting weird--with key up I see about 14 volts, and with key down I'm getting a ~4volt p-p square wave centered around 12v, and from what i can see it has a frequency of around 50 KHz. tracing back a bit i'm reading a 30V p-p square wave on pin 5 of U3 (a 13600) at the same frequency.
 
any thoughts as to what i should check next?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20050308/f4222eea/attachment.htm>