Gary sent me some notes about the STL U6-25/ U8-4 setup to no avail. (I
was already testing this with Scott after Googling around for notes on
this issue.)
After flipping through the back of the book there are some more
troubleshooting steps.
--U8-4 looks fine
--Q5 (2n7000) looks fine
--The AC Vrms on pin7 of U10 is low.
I then flipped to the voltage reference table for the Control Board and
started testing the pins for U10. DC Voltage on pins 1,2,3 are all low
and virtually nonexistent. Pins 4,5,6,7 all test out fine.
When I look at the schematic for the control board in Appendix B It
looks like U10 is quad op amp. It looks like the U10B portion of it is
providing the signal to U9. If the U10B voltages all look fine where
should I be looking next?
Scratching my head.
Thanks, JH
--
John Hoaglun
NG0R - EN25
http://www.hoaglun.com
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