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 YEAR: October 1967
 ITEM: Digital Computer
 COMPANY: Hewlett-Packard
RARITY: Exceedingly Rare   Click here for further information on our rarity scale Information on the rarity of this item is unknown.

HP 2115A

A view of the vintage HP 2115A an important part of computer history
The 2115A was introduced to take advantage of the success of the HP2116A which had been offered to the public a year earlier in 1966. According to Jon Johnston who runs the HP Computer Museum in Australia (, "The 2115A was introduced to take advantage of the large general data processing demand created by the 2116A. Computers used in general processing environments did not require the expansion bays of the 2116A. These bays were designed for connection to HP instruments and were omitted in the 2115A. An optional expander was available for this purpose. The 2115A had a very short life. While it was on HP's price list for almost five years, it was not much in demand after the introduction of the 2114A in 1968 (when the 2115A was reduced to $14,500). As a result, 2115 computers are very rare."

The 2115A had a magnetic core memory that could handle up to 4096 words or 8192 words depending upon the option chosen at time of purchase. The computer could acommodate up to 40 interface cards. The main computer unit is 24.375"L x 16.75"W x 12.25"H and weighs 65 lbs. The 2161A power supply is 18.375"L x 16.75"W x 10.5"H and weighs 95 lbs. Control cables are nothing like today's computers and are really thick and heavy (see pics).

A PDF of the tech manual is available at:

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Click on any of the images below to see the slideshow.
Front pic of the computer and power supply. Inside of the HP2115A. Cards with labels. Empty board slots. A board loaded with resistors. Boards with loaders labeled A1 through A13. From the right side center of the unit. Close-up of a slot. Tinned tracks on a circuit board. Knobs on the front of the unit. Front of the unit. Inside the unit.  Pretty, isn't it? Label on one of the boards. Motorola transistors. Inside shot.  See the TI ICs? Near the power cables inside. Side shot. Ferroxcube Corporation label. Accepted label, blank. There's high voltage here... A board with the connector on the bottom. Another close-up of a board's label. Another close-up of a board's label. There's no fuses! Inside somewhere... A lone DMA word count board side label. Ouch, those TI ICs are corroded! Front shot of the computer. Top shot of the computer. Switch register close-up. The main logo. The loader enabled switch, notice the lime buildup? Register lights. Left side shot. Rear shot. Rear shot with cable out of the way. Serial number plates. The fans on the back of the computer. Amphenol plug. Voltage outputs. Someone etched in the corresponding voltage for the plugs. The cable.  Big and heavy. Another Amphenol plug shot. A metal tag on the cable. Side view of the plug. Right side of the computer. Front shot of the power supply. Left side of the power supply. Rear shot of the power supply. The serial number plates on the power supply. Close-up of the power supply fuse and Hubbell twist-lock. Ins and outs for that big cable. Right side of the power supply. Power supply logo and light shot. Small pic of the HP 2115A.