Old Calculator Web Museum Advertising and Documentation Archive
Friden 1150 Logic Schematic
This is a logic-level schematic for the
Friden 1150 printing electronic
calculator. The 1150 was Friden's first printing electronic calculator,
introduced in February of 1968 at a retail price of $1,495. The 1150 was
the first of a series of 115x calculators, which also included the
1152, 1154, and later,
the 1155 and 1155A calculators, which were much more advanced programmable
scientific calculators, but shared many mechanical components, including
a similar printing mechanism and cabinetry. The 1150, 1151, 1152 and 1154
calculators shared a common architecture based on the original
Friden EC-130, utilizing
small-scale DTL and TTL logic, and three counter circuits in conjunction
with a magnetostrictive delay line. The later 1155 and 1155A machines
utilized large scale MOS integrated circuitry, with a microcoded architecture,
Binary Coded Decimal math unit, MOS ROM for microcode storage, and MOS RAM
for register and program storage.
The schematic includes all of the logic for the 1150 calculator
at the gate and flip-flop level.
The schematic only includes the circuitry
located on the five plug-in circuit boards, and does not include the power
supply, printer driver, delay line amplifiers, and motor start/stop circuitry.
The numbers preceded by an "M" inside the logic symbols indicates
the board number and IC package on the board in which the logic element
exists. The first digit after the "M" indicates the board number, and the
next two digits indicate the package number on the board.
In general, the package number is identified by etched notations on the
circuit board near each package.
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must include the watermark indicating its source as the Old Calculator Museum. Thank you.
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