4 inputs D.C. sense amplifier 4552D system building block
Digital Equipment Corporation (DEC)
Printed on the solder side at the insertion end of the board
Stamped into the side of the aluminum frame
Stamped into the aluminum frame on the side
overall: 1/2 in x 4 1/2 in x 10 1/4 in
The object has a green board surrounded by an aluminum frame and a blue plastic connector. One side of the board is covered in components, including resistors, transistors, diodes, capacitors, and two transformers. There are also three inputs screwed to the frame at the extraction end. There are two inspection stamps. On the face of the frame some has written "4" on a piece of masking tape. The solder side has a printed circuit with a grid lettered A-Z.