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General Electric HM-225 Restoration

The Cabinet. The cabinet is in fair condition, needing some minor woodwork and a refinishing job.

The Chassis. Here are pictures and technical information. The chassis will be cleaned with water and a mild detergent using soft brushes to get into small places. Then, all paper capacitors will be replaced with modern ones (see the procedure for this). Each electrolytic capacitor will be tested for leakage and capacity. If bad, new electrolytics will be installed inside the old ones.

There are two chassis, a power supply and the main chassis. The main chassis has been modified with a 6J5 oscillator in the socket where a 6F8 dual triode oscillator/mixer was located. An additional socket has been placed on the top of the chassis, with a 6AC7 mixer. We will return the set to its original design.

The antenna wire has been replaced with postwar 300 ohm twinlead, and a RF preamplifier has been added on a separate chassis bolted to the inside of the cabinet. We have removed the preamp, and will replace the twinlead with twisted wires.