TM 5-1260-206-34
1-15. CALCULATOR PRINCIPLES OF OPERATION - The Calculator computes the
r e q u i r e d position information of the feature observed by the operator. It
is programmed by the applicable data base cartridge and prints out the com-
puted position information on paper tape or recorded on the tape cartridge.
F o r further information, r e f e r to TM 11-6660-263-24-2, Organizational, Direct
Support, and General Support Maintenance Manual for Calculator Programmable
CP-1387/U.
NOTE
Throughout this manual calculator keys are indicated by
1-16. DIGITAL DISPLAY PRINCIPLES OF OPERATION - T h e Digital Display provides
a LED read-out of both the X- and Y-coordinates of the photo-carriage cursor
c o i l relative to the data grid. The read-outs provide a resolution of one
one-thousandth of an inch.
1-17. DAC PRINCIPLES OF OPERATION - The DAC is functionally located between
the OMS and the Calculator. I t accepts the analog position and elevation data
from the OMS, converts it to digital data , and provides it to the Calculator.
I t also provides for the relay of information from the Calculator to a tele-
type circuit.
a. F u n c t i o n a l Description - The DAC consists of seven printed circuit
cards and a power supply. Each printed circuit card has an 86-pin edge con-
n e c t o r with pins 1, 3, . . . . 85 (odd numbers) on the component side and pins
2, 4, . . . . 86 (even numbers) on the back side. 110 volt ac primary power
c o n t r o l is provided by the power distribution assembly. A l l system inter-
connections are made on the rear panel.
Theory of Operation - The DAC is composed of:
b.
Power Supply
Digitizer Control (D) Card
Analog (A) Card
Axis (B & C) Cards
Multiplexer Storage (F) Card
Control (G) Card
(1) Power Supply - The dc power supply provides +5 volts, +15 volts,
and -15 volts to the DAC circuit cards and +5 volts to the DIC and Digital
Display assemblies.
( 2 ) Digitizer Control (D) Card - T h e digitizer control (D) card
g e n e r a t e s the following signals:
Clock pulses
Clear Logic
Hold Logic
1-15