This is a 1960s Univac Memory Stack Module unused and in original Styrofoam case. Purchased at a military surplus auction, it was for the MK152 military computer that controlled the Weapons Fire control systems. Research reveals that Univac introduced the 418 model often called the Univac 1219 for commercial use. With government modifications the same machine became the MK152. Removing the back panel shows the memory which appears to be two sets of laminated encased memory modules each 1.5” thickness. It may be core, rope or ribbon memory. Further research shows the Univac 1219 / MK152 was an 18 bit word memory machine. A historian sent us the following:
“The Univac 418 / 1219 computers were announced for business use in the 1960s. A military facsimile was also developed and used on surface ships for control of weapon systems. It was called the MK152 computer complex and used on navy ships. There was 18 bits per byte which could be dueled out to 36 bits. Discrete components on cards contained dual gates i.e. two nand gates. Each instruction took from 2 microseconds upwards. Read/write currents into core memory were very critical. Even though memory was destroyed on read an immediate rewrite returned it. It took two of these modules for 64k of memory. Standalone external was possible using I/O channel for access. Front console was very colorful showing internal operations showing registers, memory address, interrupts, etc...”
The top of this stack has Univac Plaque and is stamped: “Sperry Univac Memory Stack Module 90536 Assy 7093362-01 Rev AA Ser. 3364”. The Size is 5.50” high x 7” wide x 5” length & 7 lbs. Computer antique collectors will find this a highlight to their collection.