Vintage Lego Technic

I'm helping out a local charity with their annual Lego fundraising sale, and this 30 year old Technic kit came through for me to check.

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It has an electronic controller, and the heart always falls when you pick it up and can feel the weight of 30 year old batteries still inside. Sure enough, the batteries had leaked and corroded, all over the place. This is usually not something we can sell, especially when they have leaked this badly. This will usually have corroded and ruined circuits underneath.

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However, I have to admire the design of this controller - the battery bay was completely separated from the other circuitry, with only a tiny amount of leakage getting through to the back of the PCB. The front of the PCB has no damage at all.

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Hot wiring the controller to a 9v supply shows that everything still functions. Buttons control 3 motors, and you can program in a sequence of movements to be replayed later. There's a little Motorola chip doing the work.

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I managed to pull the battery contacts out and cleaned them off with a small flat screwdriver, and some vinegar. Once I got the corrosion off, it became obvious that the metal has been eaten almost through. You can see daylight through some bits. This isn't going to be useable.

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I've ordered some new battery contacts and will put them into place once they arrive. The kit will then go to some lucky person at the sale (it should sell for $200 or so we hope).