Model 45 034, S/N 00153

A gift from Dennis S. Bernstein, 1 August, 2018

The Electronic Associates, Inc. TR-48 is a general-purpose analog computer built using germanium transistors, and first shipped in 1961. The TR-48 is a called desktop analog computer, but since it weighs more than 400 pounds you need a strong desk. The TR-48 originally sold for $25,000 and at the time, was considered the best general purpose analog computer on the market. Ours has the optional 'scope display with a very slow phosphor. The TR-48 was large and powerful enough to solve most engineering problems and can still be powered from an ordinary electrical outlet.

We need to count the amplifiers in the system. It can hold a maximum of 48 amplifiers.

The grey device below the 'scope is a transistorized digital volt meter.

Programs were created by installing patch cables and jumpers between the analog components in the computer.

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The front of the EIA TR048.

Current Condition:

    • The 'scope does not work

    • About 1/2 of the amplifiers do not work

    • The motor drive that clamps the patch panel in place may not work correctly

    • It needs some minor mechanical repairs

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The green device near the top of the image is the motor that engages the patch panel.

We have four patch panels for this system, so you could leave a "program" on a patch pane for future use.

The force required to install a patch panel is so high, that it required mechanical assistance from the motor.

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The Model/Serial Number tag from the EIA TR048.