Gottlieb Early System 80 Head Locks

A useful video, found via Pinside, on how these are supposed to work.

I have a Counterforce that has been sitting idle since we moved to a new house. I got it set up and noticed some score digits were out. No problem, I know exactly what the problem is: I have connectors that I have not serviced. I opened the head to jiggle them.

When I went to open the head, I noticed that the key was easy to move, as if there was no lock mechanism. What actually had happened is that I did not tighten the screw sufficiently when I re-keyed the lock, and having the game on a truck for shows and a house move jiggled the screw out of the lock.

When I first got this game, I remember changing the lock. I only change head locks when I can’t find a key. On this game, I think there was no lock or the lock was defeated. I changed it to my keyed-alike lock, and forgot how the mechanism works.

In short, the mechanism on these early System 80 games moves a crossbar down and forward, which pushes two (sprung) arms forward. When the arms are in the forward position, you can’t lift the backglass.

On Counterforce, there is an extra wrinkle that the speaker mounting is in front of the lock, but a long screwdriver is very helpful in getting the screwdriver in the right place.

Note that it is useless to tighten the screw when the lock is unlocked (assuming my usual Fort locks, which will not release the key in the unlocked position). And, when the insert panel is fully open, it prevents the head from being locked (the crossbar intentionally interferes with the insert panel). However, if the insert panel is only somewhat open, I can lock the head, pull the key so the lock doesn’t turn, and then crank down on the screw.

Even by the standards of this blog, which is an absolute backwater of the Internet, this post is of very limited utility. But here it is.

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