Archived from groups: rec.games.pinball (
More info?)
"Robblv" wrote:
> The flicker is a steady "pulsing" that did not occur on my older Kiss
> machine.
>
> How do I adjust the voltage at the solenoid driver board?
The pulsing could be low voltage coming out of the high voltage regulator on
the solenoid board- adjustable (see below).
Or you could have a failing filter capacitor in the HV regulator circuitry.
Either can cause what you're describing.
To check the voltage going out to the displays, use a volt meter with
negative lead on a ground point, and touch positive lead to TP2 which is in
the high voltage regulator circuitry in the upper left corner of the
solenoid/regulator board. Usually you have to reach the test lead up
underneath the protective plastic that mounts over the heat sink in this
area- in order to get to TP2. So be SUPER careful not to touch any other
components or short anything out.
Voltage in this area on the board is as high as 250vdc, so use EXTREME
caution- the wrong move can damage something or at worst kill you.
You can also check for the same (TP2) voltage at the TP2 test point on any
of the 5 display units (if that's easier to get to for you).
Voltage at TP2 should be in the range of 175vdc to 195vdc. You can increase
or decrease the voltage by adjusting the small pot (knob) near TP2 and TP4
on the solenoid/regulator board. Do this with a small screwdriver while
watching your meter reading (while connected to TP2) to see how you are
adjusting the voltage.
This may clean up the strobing or pulsing you are seeing. If not, you might
consider replacing the large electrolytic capacitor mounted at the top of
the board (horizontally). Original type is hard to find or may not even be
being made anymore, but what we use is a standard off-the-shelf 160uF 400v
cap and it does an excellent job of filtering the DC voltage in this
circuit. And will far outlast the original cap.
Hope this helps!
Ray J.
--
Action Pinball & Amusement, LLC
Salt Lake City, Utah USA
Web: www.actionpinball.com
We're serious about pinball. Anything else is just for fun!