How to Clean Old Tube Radio Circuit Boards
- 1). Unplug the radio or amplifier. Remove the screws that fasten the top, side, back and circuit board panels in place. Make a rough sketch of the circuit board or chassis showing the location of each vacuum tube.
- 2). Remove each vacuum tube from its socket and record any numbers etched in the glass or printed on the base of each tube onto the diagram so you will know where to re-install the tubes after cleaning.
- 3). Use an old dry toothbrush to loosen dust and debris while you blow it away with a canister of compressed air. Use caution to avoid bending wires or breaking soldered connections.
- 4). Use alcohol wipes or isopropyl alcohol and cotton swabs to very gently wipe each component and any exposed surfaces of the circuit board. Do not saturate. Use compressed air to blow away any further dust and debris accumulated and to evaporate thoroughly any alcohol residue.
- 5). Use a clean dry cloth to wipe each vacuum tube clean. Refer to your sketch to replace carefully each tube into the same tube socket from which it came.
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