This part is a kind of semiconductor called KRC-379R.
Function of this product has (KRC-xxxR) Cassette Receiver.
Manufacturers : Kenwood
Image and pinout :

Some of the text within the PDF file :
KRC-479R KRC-379R KRC-35R CASSETTE RECEIVER INSTRUCTION MANUAL B64-1820-00 (EN) Contents English Safety precautions3 General features Power5 Volume ..5 Attenuator .5 Switching Modes ..6 Loudness ..6 System Q .. [ ... ]
KRC-379R PDF Datasheet Download
