Robotron issue

lintzgm

Active member
Joined
Nov 7, 2008
Messages
630
Reaction score
29
Location
CHAPEL HILL, North Carolina
Ok not sure whats going on with the Robotron. Its showed a Ram error at loc 37. Last night I relplaced all the ram and re-adjusted the colors on the monitor..it was a little off. Worked perfectly and played it for hours last night. Now today I turn it on and had all the monitor colors gone besides blue. Tried to adjust with no luck. Then the monitor goes to red with some lines reading an error but I can't read it. Its flashing 3 and 1 on the board so I replaced that ram still nothing. It has a switcher and all the voltages are right on. I did order a get well monitor kit for the monitor going to do that but not sure what's going on any ideas?

Jeff
 
Last edited:
I just bought this game back from the person I sold it to 6 years ago. I put a switcher in it about
8 years ago. What's got me is it seems to be something with the monitor but that's a long
Shot.
 
That ribbon cable is always a suspect. Like maybe when you had the board out to replace the ram, the ever-aging cable finally gave up the ghost. I just replaced that on my Defender, and just the other day I went ahead and got an extra one from Bob Roberts to have on hand.

Often I'll put a mirror in front of the game to see the monitor, and push on chips and wiggle cables looking for changes.

On the ram - I highly recommend the conversion to 4164. They've just been absolutely bullet-proof in my Williams games.
 
Check the voltages on the RAMs you can get some strange color issues if the 12V is off. Voltages at the RAM should be:
-5V, +12V, +5V and ground (pin1, pin8, pin9, pin16).

Switchers tend to drift over time and need to be readjusted every couple of months. Also it is not uncommon for the other voltages to drift even if the +5V stays the same.

ken
 
Back
Top Bottom