The Wizzards are great. Some service tips.

After 20 years, usually less depending on the humidity, you get a faint bit of corrosion on the chips that are socketed and the machine becomes temperamental. The solution is to open it and ONE AT A TIME, remove every socketed item and connector and then reinstall them. Be careful with the chips so a pin does not fold under the chip. The socketed chips are EPROM's and if not perfectly programmed can loose bits after a long time. They may have to be read multiple times to verify the read and reprogrammed with the verified data. They keep the programs by a static charge, that makes them time vulnerable.

The motors have a coil and capacitor set mounted in them to reduce the interference to the machine. It does that well but burns brushes and the commutator fast. You can usually replace the brushes three times before the commutator burns too much. A matching motor with those parts added will work well and be far cheaper. Also adding a 10 ohm resistor in series with the grounding capacitor there will not affect the operation but will increase commutator life a lot.

A bad brush/worn commutator can also make the machine temperamental due to the excessive arcing glitching the program during operation.

Philadelphia, PA (Really Bensalem)

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