Note
Bud Radio catalog 124, undated, p. 2.
Radio, Jan 1940, p. 138.
Radio’s Master, 9th edition (1942), p. H-106.
QST, Jun 1947, p. 143.
This is the same device as the CPO-124, but without a headphone jack and pitch control. A switch selects high or low pitch. There are connectors on the rear panel for connecting an additional key and speaker.
Optional additional extra matching speakers:
CPO-121, with magnetic speaker.
CPO-123, with dynamic speaker.
Brief review: Radio, Jan 1940, p. 138.