These games are up at Hoots Roller Bar in Winston-Salem, along with a Williams Rollergames. Great line-up of games that do change from time to time, definitely check them out in the Winston area!
I was originally contacted about Party Zone having a blank display. Turns out the DMD Controller Board was missing one of its key voltages — +62VDC. I had some parts for the HV section on hand, but was missing some of the key components. In an effort to keep the game up for a large event, I sold my working DMD Controller board out of my Fish Tales and kept the in-for-repair DMD Controller at home and ordered parts (look out for the post on DMD Controller board rebuild next week when parts are in!)
With display up, I checked a few other parts of the game. The owner mentioned the Captain Bizarre head wasn’t spinning, so I did some sleuthing on that and found two columns of switches were not registering. Since the 2803 was socketed, I dropped a new one in to see if that did the trick. It didn’t, so I pulled the board and started buzzing continuity. A lot of these WPC games can loose continuity over time in the switch matrix, I’ve seen it quite a bit actually. So, whenever you’re missing a row or column, remember to check continuity before shotgun replacing chips!
The missing columns were column 5 and column 8. Turns out the connection between U20 pin 11 and R74 was missing and U20 pin 14 and R71 was missing as well. These pins of U20 travel through the resistor/capacitor chain to the male pins of J206-8 and J206-5 which go on to the playfield switches.
I tied jumpers between these connections and Party Zone was back registering all switches in game and the DMD was back crisp and bright.
Earthshaker’s issue was that the pop bumpers were not working, all three of them. I checked the voltage at the coils and it was essentially nothing, milivolts. However, the fuse on the auxiliary power driver board that supplies the 25VDC was fine and the connections looked fine. Even the Quake motor, left slingshot and right slingshot which are on the same power line were fine.
For a second, I was scratching my chin on this one, but then remembered that Earthshaker has an under playfield fuse behind the pop bumpers that lines directly to them. It’s kind of buried and hard to see, but this 2 1/2 amp slow blow fuse was for sure popped. Once replaced, ES was back to speed.