This is an archived website which has not been updated since 2002.
Some information may be inaccurate or out of date.
Restoring Old Radios & Televisions
Decoding Valve, Transistor and CRT Numbers
Note that at least three, entirely different, series of valve designations begin with the letters VT (US Signal Corps, British Royal Air Force and British Post Office). This can be a major source of confusion, although not if you know the source of the device in question.
Buyer's Guide has now moved to the excellent Radiocraft site at
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