TM 11-6625-3081-23
1-13. DESCRIPTION OF TEST CONSOLE TEST BENCH 2A2 (cont)
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c.
PROGRAMMABLE DIGITIZER ASSEMBLY 2A2A1
(1) The programmable digitizer assembly 2A2A1 (Tektronix 7612D) consists of a
mainframe, mounting provisions for two programmable plug-in amplifiers (Tektronix
7A16P - preamplifier), and a rear panel mounting for the interface assembly 2A2A1A1.
(2) The digitizer is a microprocessor-based, dual-channel, waveform-digitizing
instrument that analyzes waveforms in lieu of using an oscilloscope.
It is located on
the front of the test console test bench and is rack mounted using drawer slides.
(3) The mainframe consists of the time bases, triggering circuits, controls,
displays, and functions as the IEEE 488 bus interface for the programmable plug-in
amplifiers.
The front panel provides total control and is divided into three main
control (function) groups that are panel color coded.
These are:
Function
Panel Color
Instrument control
gray and yellow
Time base
blue
Trigger
green
(4) A CCA (2A2A1A56) containing two address selector switches is located inside
the unit.
It is accessed by removing the programmable digitizer top cover assembly.
(5) The rear panel contains 11 coax connectors, an IEEE 488 bus connector, a
power switch, a fuse, and a fan.
The fan forces air over the heat sensitive digital
electronic circuitry.
(6) Two identical programmable plug-in amplifiers (channel A and channel B) are
installed in the digitizer.
They provide display and trigger output signals to the
digitizer.
(7) The interface assembly 2A2A1A1 is mounted to the rear panel. It is powered
by a direct current input and provides a fixed 200 megahertz clock signal output to
the digitizer.
This signal drives the channel A and B time bases.
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