The Packard Bell PB-250 is a 22-bit mini from 1961. It was built by the computer division of Packard Bell Electronics, which is not related in any way to the current Packard Bell company that makes PCs. The PB-250 uses magnetorestrictive acoustical delay line memory made by Ferranti for main store.

Directly below the CPU is the Power Supply, and beneath that, our PB-250 is configued with Multiverter, Digital To Analog, High Speed Buffer, and Ampex Core Memory units.

The CPU keeps a running total of hours in use.


The CPU is constructed using a number of very simple logic boards, with a custom wired backplane to impliment the PB-250's logic. The backplane is soldered, rather than wirewrapped, and each socket is keyed to only allow the insertion of the correct type of board.

It has a very minimal front-panel built in:


It primarily relies on the console Flexowriter for many of the operations one would expect to be on the front panel for a machine from its time.

The PB-250 was part of a hybrid digital/analogue computer called the Trice system offered around 1960 by Packard Bell Electronics.

We currently know of only three PB-250s still in existance:

Ours (The Retrocomputing Society of Rhode Island)
Paul Pierce's
The Computer History Center's

An excellent recollection and description of the PB-250, from someone who used one in a production environment.

Go to the RCS homepage.
Return to Dave's RCS page.
Return to Dave's homepage.