Let's Do A Time Warp Again.

[xman]

Many of you know I do arcade machines but few of you know I was one of the last if not the last Australian to be taught component level repairs on pinball machines when I left school. This was my true love, pinballs and to be taught by the best from the three US based pinball manufactures when I was basically an addict to these machines was a dream come true when I first left school and to be paid money by way of a wage was icing on the cake for me. Anyway, years gone by now and after refurbishing and selling about 70 pinballs, I have another to refurbish in the man cave. It is a 1979 Williams Electronics Time Warp.
http://www.ipdb.org/machine.cgi?id=2568

It isn't mine, it is my mate's that is also my auto electrical and this job is as payment for the upgraded lights he fitted to vehicles.
It wasn't booting up at all when I got it but after a couple of hours it is at least starting up. To get it to boot up required removing the cheap and poor quality IC sockets these 3 ROMs were mounted in and replacing with machined pin IC sockets.

These are the new IC sockets soldered in place. Cost about $2 each but will never fail again.

Board back in place and now it boots but the machine still has issues as expected.

Most notably, the displays are not all working. These are plasma displays that run on 170vDC. The issue isn't the displays themselves thank God, they are near impossible to get spares for now.

I think it will be the large 40 pin IC in the top left board as it is the PIA chip, a 6821 that drives the displays. The two that look the same on the lower left board are the same part however they aren't on sockets or I could simply swap the chips and see if the problem travels from being a display problem to becoming a coil driver problem or a lamp driver problem that these two lower chips control. I have the replacement 40 pin sockets and will swap all the PIA sockets next week when I have time. I'm really enjoying working on US 70s technology again instead of 2000-2015 Chinese boards. Over heating boards while soldering and de-soldering is near impossible. Also early Motorola based machinery is very logical in it's operation. The whole system Williams are using is 6800 Motorola based and the parts are still cheap and available also very reliable. It's also good to work on stuff that was designed to be repaired.

[professor_jonny]

All modern electrics is often throw away no one gives you circuit diagrams all board swap type repairs, and people you take things to charge 50 to look at it+ min 1 hour charge for putting a plug on the end of a drill for example.

It really does my head in I get called the guru at work as everyone drops off thee broke stuff for me to repair and payment is usually cake or scones for smoko!!!!
I aplaude your efforts' it is a skill being lost these days.

[asbo]

Lovely to see components and traces you can see with the naked eye! OK a slight exaggeration but being able to tell a resistors rating by looking at the colour bands is nice

[spicemuseum]

Lovely to see components and traces you can see with the naked eye! OK a slight exaggeration but being able to tell a resistors rating by looking at the colour bands is nice

I wonder how big Jonny's AVIP breakout board would be if it didn't use surface mount 'dust' ?

[professor_jonny]

It would not happen you cant really use thruhole components not enough space to do it.

[asbo]

I'm sure you could break it out to nice external box and use wire wrap components

[spicemuseum]

So long as the wires are adequately shielded against interference.