Cgs synth

hello, I built the CGS VCO(ver.4). Took me a couple of years collecting the parts and finally putting it together on the PCB board i got from Ken Stone, and it didn't work. All I got was a loud hum. The problem is I'm not an engineer and don't really have a good understanding of what's going on so I haven't got a clue of where to start troubleshooting. Is there anyone on the list who would be interested in troubleshooting this, for a fee of course.
You can email me at: smcmanaman@...

thanks a lot,
steve