Hey Frank,
The -22V supply does have an adjustment, and the 5.2V supply is derived
from the -22V supply. It turns out that -20V/-22V*5.2V is ~4.7V, so the low
5.2V supply is likely down to the low -22V supply. Did you try adjusting
the -22V supply?
Siggi
On Thu, Feb 15, 2024 at 6:53?AM Frank Mashockie <fmashockie@...>
wrote:
@Harvey
Left the lab for the day, but I did check the voltage drop across that
resistor R624 0.33ohm. I can't recall what it was off the top of my head,
but I'll let you know tomorrow. I thoroughly tested both power supply
circuits on the SG503 and if there is an issue, it must be something
loading down the supplies like you suggest.
However, I injected ~5.2V into the unit with an external power supply - it
did not fix the display issue. No difference whatsoever. It may be that
these are the normal voltages for the unit when it is powered from a TM5000
series mainframe.
I'll be taking another look at it tomorrow! Grateful for any further
suggestions as well!
-Frank
-Frank
