9720 VCO assembly problem‏
Page 1 of 1

Author:  Nic Roche [ Sat Dec 12, 2015 6:58 pm ]
Post subject:  9720 VCO assembly problem‏

We have finished assembling all modules. We are doing the end-to-end tests.

We are up to Testing #3 on VCO. We have roughly double the period on the modulator cycles.
    Modulator attack midpoint - ~4 instead of 2 seconds
    Modulator release midpoint - ~10 seconds instead of 5 seconds
    Attack and Release fully clockwise - ~29 instead of 15 seconds

We have verified the correct value transistors Q4-Q6.
We have verified the wiring and resistor value on R200-R202.
We have verified the correct voltage at IC3 pin 4 (+12V) and pin 11 (-12V).

There were no other verification's listed. Was there something else we could have checked?

Also, on the next step #4 we get on AC the correct reading (1.25V) but on DC it varies wildly. These problems may be related.

Page 1 of 1 All times are UTC - 6 hours [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
./cache/ is NOT writable.