TitleWhirlwind 305 step counter
DescriptionObject is a large panel bearing sockets for 53 vacuum tubes (36 populated). Engraved front top center and on a label on the rear lower right is "305 STEP COUNTER SERIAL #1". Around the perimeter of the front are 49 BNC connectors. Each has an engraved functional label on both front and back of the panel, some examples being "J-809 DIVIDE IN", "J806 SHIFT LEFT OUT", "J103 TEST RESET". There is a 29-pin male connector lower left. The rear supports a number of phenolic circuit boards elaborately wired with resistors and capacitors. At the top rear is a row of 12 clear pilot lights.
A paper label on the front reads "NR3703 - BOX 1 - #6". However, the object matches in every respect the photograph hand-labeled "NR3703, Box 1, #4"
ManufacturerMassachusetts Institute of Technology (MIT)
|Model number||305||Black label rear lower right|
|Other number||C15-3||White gummed label rear lower right|
|Serial number||1||Black label rear lower right|