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Valley Spectra IV Pinball Game:

It's been a while since I worked on any serious electronics projects - either construction or repair - because most modern electronic devices are pretty much throw-away - 'No user serviceable parts'.

So when a friend of mine asked if I'd look at an old pinball machine to see if I could get it running, I jumped at the chance. Here is technology I understand and enjoy and an opportunity to get my hands dirty once more. I love machines and electronics and this vintage of pinball combines them in a form that is still access able ( read: 'repairable').

Troubleshooting and Repair.

  • First Pass (2012):
    Repair notes and pictures showing progress bringing one machine back to life. Many of the BLOG's and chat sites list this machine is 'Better left alone and used as a card table.' I think it's a great machine and well worth bringing back to life. There aren't many around and if you have one - either working or used as a coffee table - please let me know (with pictures).

  • Second Pass (2021)


Since originally posting this I have had calls and email's from others with similar machines and/or problems ( I must be coming up on Goggle - sneaky me). There isn't a lot on the web about some of these less common machines and I welcome the chance to dig in and share what I learn.

Are there other options to recovering the original brains of these things?

It seems like I'm getting more and more contacts regarding these Valley Spectra IV machines. One web site I found says the only use for these machines is a coffee table. I agree that they make nice tables, for playing games and such, but wouldn't it be nice to have it work. Most of the enquires I get are like; "Do you have the ROM listing that I could get?" Or else like; "I have a few of these processor boards laying around, would you consider combining our stock to see if we can get one that works." But why not just re-design the motherboard? How hard could that be? It's just sensing contact closures and then turning on a switch (to fire the solenoid), with a background set of counters to keep track. And another circuit - and process - to drive the displays with the scores, etc.

So, I'd be interested in hearing what anyone is doing in reverse engineering these things. Meanwhile I am ramping - and refreshing - up my own programming and processor board design skills by playing with some development kits, etc. Just the beginning of my search for the right platform to do something like this.

I know this isn't as elegant as fixing the original but the design of these originals really sucks and the ones I've seen have been hacked all over the place. Maybe the pinball gods would forgive some meddling.

Some links to pinball sites of interest (in no particular order):