Need help: DSD-440 with unresponsive formatter/control board

[Jerry Weiss]

On Sep 20, 2016, at 2:02 PM, Julian Wolfe <jrw at lolqb.us> wrote:
> 
> After reading this section, I should probably bring up that when I checked the PSU voltages, the 5v+ line was low, at 4.7v or so.  I adjusted it back to 5.05v on the pot as defined in the manual, and there it stayed steady, but it didn't seem to help.  Before I adjusted the pot, it was fluctuating.
> 
> 

Given the age of the unit, its not surprising that the potentiometers are a noisy, have drifted/aged and/or are contaminated with crud. 

SYSTEM Reset L should be High.  If Not then Check for 1.1V on THR.