3909679 is referenced by 24 patents and cites 3 patents.

A solid state amplifier for automatic coin-controlled phonographs mounted within a dust sealed cabinet and comprising a cast aluminum chassis having one wall formed with heat convecting fins mounted over an opening in a rear wall of the cabinet such that the convector fins thereon are exposed to atmosphere exteriorly of the sealed cabinet and having heat emitting power transistors of the amplifier supported in thermally sealed chambers between a heat sink support for the transistors and the interior of the finned convector wall of the chassis to provide efficient convection cooling of the transistors while preserving the sealed integrity of the cabinet's interior.

Cabinet and heat sink for amplifier components
Application Number
Publication Number
Application Date
November 7, 1974
Publication Date
September 30, 1975
Petri Ralph E
McCaleb Lucas & Brugman
Rock Ola Manufacturing Corporation
H05K 07/20
H05K 07/20
G07F 09/10
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