Artifact Details


38503-1 cartridge storage unit

Catalog Number



Physical object


Control Data Corporation (CDC)

Identifying Numbers

Model number 38500 Large label on right hand door
Model number 38503-1 Label on right hand door


overall: 78 1/2 in x 70 in x 20 1/2 in


Object is a large cabinet. The left two-thirds has a 30 x 36 array of openings for 1080 cartridges. A selection device on rails moves in front of the cartridges. Windows in the front doors allow watching the selector at work.

This CSU unit is used with the CDC 38500 tape cartridges and is part of a CDC Multi-Access Storage System (MASS). The back of the unit has 2 small access doors near the top. This allows 2 Mass Storage Transport units to be connected to the CSU. A sign on the front indicates the the MASS can hold 16,000 cartridges which is about 16 times the number which can be held in this unit. One end of the cabinet is open and has a large steel alignment pin sticking out at the bottom. It makes sense that a "mirror image" cabinet would connect to this cabinet making up a full CSU. A full capacity MASS would be made up of 8 CSU's.

There are four 7 by 8 inch magnetic backed signs stuck to the outside of the unit. The one which reads "CSU 0" is stuck to the left most front door. This is assumed to be the unit's actual designation. The other three signs which are stuck on a back door read read "CSU 1", "MST 11" and "MST 23". It is assumed that they were taken from other parts of the MASS system when the other parts were being scrapped.


Memory & storage/tape


Gift of Lawrence Livermore National Laboratory (LLNL)

Lot Number