Stern Lectronamo Pinball Repair

Introduction

This is one of my games that I got in a recent purchase. I didn’t have the chance to test the game onsite, but knew it didn’t work. A quick look at the game showed that it was complete and in decent shape.

Head of the Game

When I finally had a chance to look at this game, it’s body was buried behind a couple other games. I was able to pull the head of the game out and start looking at the boards inside. One of the first things I noticed was the original battery was still on the MPU. There was extensive battery corrosion, and at that time I ordered a replacement one. I went ahead and removed the Solenoid/Driver Board (SDB), Lamp Driver Board, and SB-100 Sound Board for further repairs.

SDB

I went through the SDB and added new caps along with adding a couple of jumpers on the backside of the board. I also tested all transistors and replaced a couple of resistors and diodes.

Lamp Driver Board

I tested all the transistors on the board, and all were good. To my surprise, battery corrosion had leaked on to this board and had three green transistors. I went ahead and cleaned up the battery corrosion and replaced three transistors.

Sound Board (SB-100)

I went ahead and re-soldered the headers pins and installed new caps on the board.

Displays

I pulled all the displays and checked the 100K resistors along withe re-soldering the header pins. With all of the boards gone through, I went ahead and dug out the body of the game for its initial test.

First Power On

The cabinet had a broken “neck” and needed fixed before installing the head onto the cabinet. After hooking up all the connectors, I started a game. The game booted up on the first try, displays working (mostly), and attract lights were flashing. However, I could not start a game. Game had credits on the machine but the start button was not working. I verified this in the switch test. One other problem that I noticed was the coils were not firing correctly. The right sling shot and outhole would fire for different coil test.

The game started and all coils fired correctly after re-pinning the J2 and J3 connectors. J4 connector was also replaced. All three connectors had extensive corrosion on them.

Displays (Again)

Most of the displays had some sort of problem. Either a missing segment, a missing digit, or flickering. I brought the displays back out of the machine and ended up replacing some resistors, transistors and decode chips. I don’t know if it helped or not, but I did end up re-pinning J4 on the MPU board.

Conclusion

This was a fun game to work on and needed quite a bit to get it up and running again. The backglass did have some damage on it. Some of the blue on the edges was starting to peel, and I lightly sealed the backglass. Lectronamo was Stern’s first game to produce digital sounds. The game has some neat shots on it including drop targets, which are always a positive in my book.