TitleWhirlwind vacuum tube module FF MOD IV
|Serial number||20||Stamped in white ink between the vacuum tubes.|
Dimensionsoverall: 5 1/4 in x 1 5/8 in x 9 1/2 in
DescriptionThis plug-in module is formed by an open chassis on three sides and a Bakelite plug with 24 flat contacts on the fourth side. A handle is attached on the end of the chassis opposite the connector. A flange on each side holds a captive screw used for securing the module into one of the positions of the ten-module rack.
Two vacuum tube sockets are mounted on the same end as the handle. Three pairs of phenolic solder terminal strips span the space between the two sides of the chassis to which passive components are soldered; there are also components stuffed between the terminal strips. Point-to-point wiring connects the connector, the tube socket pins, and the solder terminal strips.
The tube complement is two Z2177.
An index card is Scotch-taped to one of the open sides and "NR3138 - Box 4 - #7 2 FF MOD IV" is written in red ball point pen.