I've tried, but I can't get my classic controller working anymore. It has been flaky and had some dead digits on the 8 segment LED displays. I touched up the soldering on them and got all the segments to work, but the system was still flaky, sometimes turning on with odd number segments lit up, and occasionally firing on power up if the leads had continuity. I could usually cycle the power and get it to work correctly. It counted down and fired correctly on several test runs. Then for some reason it started hitting the relay as soon as I hit the start button. I've looked for any contamination on the components and the runs on the board. I've re-seated all the chips. It got wonky about 20 years ago and I replaced all the socketed parts like the 555 IC's and such. I may try that one more time. I'm no electrician, much less an electrical engineer. I can read simple schematics, so I can slowly verify everything is wired correctly on the I/O board, but that's about it.

It was designed and built for me by my cousin. He needed a project in one of his electrical engineering classes so I was only out the cost of surplus Radio Shack parts (his dad owned one for a while). He went on to work on EF-111's and who knows what else at Warner Robbins AFB. Sadly, I haven't seen him in nearly 40 years. He and his brother introduced me to model rocketry.

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I love sanding.