Code Practice Oscillator CPO-120

Introduced in 1939, the Bud CPO-120 uses just one tube. That tube, a 117M7GT or 117L7GT combines a half wave rectifier and audio output in a single tube envelope. The tube filament, at 115 volts, can be directly fed from the power line. Two code keys can be connected to the oscillator. One key jack is on the front panel and another on the back. Pin jacks are located on the back for an extension speaker. With an extension speaker and two keys, two individuals can practice sending and receiving Morse code together.

This unit uses line-derived high voltage directly on the key contacts and phone plug and is dangerous regardless of plug orientation.  It should not be used without modification.

See also the information on the later Bud 128B with a somewhat safer keying circuit which uses a free-running oscillator and keys the secondary of the output ttransformer.

In questo link sono elencati 15 modelli, di cui 13 con immagini e 2 con schemi.
Elenco delle radio e altri apparecchi della Bud Radio Inc.; Cleveland (OH)