Star trek, the next generation

The guns are now back at the playfield, with the new wire looms. As I wrote earlier I made some changes to the LED’s  in the guns, but I had to give it up. The LED’s gave the red light dome an amber color which looked all wrong. But the biggest problem was the ghosting, so I used 555’s instead and now it lights with the right color and no ghosting.

 

I did also use LED’s as replacement for the four colored lamps in the top left corner. The light is fine but there are some ghosting problems also here. The green led in the picture is actually turned off but it is still glowing. I haven’t yet decided what to do about it. I could keep the LED’s, replace them with colored 555’s or 555’s with colored rubbers.

 

The VUK’s was disassembled and cleaned before reattached to the playfield. I checked the soldering of all optos but I need to figure out a way to test each of them once the units are in the play field. 

Cleaning the underside ball guide was quite a project. It wasn’t the dirtiest unit I have seen, but close. It was a couple of hour’s job and it came out quite nice in the end. The plastic ball guide has a repair by the Neutral zone entry. It’s nicely done by metal and there is no reason to do anything with it, but I think the cause for the damage are that people have lifted the playfield with the balls still inside causing them to fall back from the VUK’s and slam in to the end of the plastic ball guide.

 

The left stand-up target by the Beta quadrant ramp had a broken rivet. It was replaced by a screw and nut, an easy fix.

 

The trigger in the gun handle felt a bit odd and I took it apart to see what’s wrong with it. It was the return spring that was broken. I replaced it with a new spring and the trigger was OK. 

The left flipper button didn’t work in the video mode and the cause was a broken opto. I could see that the LED was lighting by using a camera and watching it in the display, but there was no output signal from it at all. I must say that being able to turn to the left gave the vide mode a new dimension J

And the most important fix of them all, moving the batteries to an external holder. I removed the old holder completely to make sure nobody makes the mistake to insert batteries in it. Leaking batteries are the single most common reason for a CPU board to be scrapped.