This module has nine (9) socket positions and all are populated. The tubes in positions 1-4 and 6 are medium sized, the rest are small. There are eleven PC boards with passive components below the tube sockets, which are connected to three male parallelogram shaped connectors at the rear. There are five inspection stamps on the top center of the frame.
Date
ca. 1958
Manufacturer
International Business Machines (IBM)
Identifying Numbers
Other number
3087607 002439
Stamped on top center of frame in black ink
Other number
6543 6544 6545
Written on white circular label on left inside of handle
Other number
D 3087607 002439
Printed on first line of paper label on front of handle
Other number
ZB B02 B X
Printed on second line of paper label on front of handle
