National Panasonic RV-2500S
The RP-2500s was a cassette dictating machine manufactured by the National Panasonic Corporation of Japan and available during 1973/1974. It usually came with RP-2590S and RP-2591S remote handset speaker/microphone, and remote foot switch. This article shows the circuit diagram, and socket pinout, which might be useful for repair purposes.
RP-2590S Socket Pinout
RP-2591S Socket Pinout
