SECTION E - GENERAL OPERATION AND DESIGN
E-1.
General
The AMPTEC RESEARCH 620A-4 Igniter
Tester is shown in block diagram form in Figure
E-1. All diagrams and information disclosed in
this chapter is proprietary and is included in
order to make troubleshooting to component level
possible.
The AMPTEC 620A-4 series Igniter Tester
uses modern solid-state semiconductors
exclusively and digital CMOS circuits
extensively to minimize power requirements
and make battery operation useful and
practical. AMPTEC also maintains a spare
parts inventory of all components found in the
620A-4 Tester and its customer service
department can also provide additional
assistance in the trouble shooting process.
E-2.
Troubleshooting
Since the 620A-4 Tester is used to test potential
deadly explosive force detonators and warheads
of missiles etc.,
personnel that are not qualified
to make such electrical repairs on the 620A-4
Tester should not even attempt to remove the
calibration access screws or open the main
panel or effect any repair whatsoever
.
Apparent 620A-4 Tester malfunctions can
sometimes be the result of bad test
lead/connection wiring, wrong connections,
misinterpretation of specifications, low battery
levels, and in rare cases due to an incomplete
understanding of the instrument and how to use it.
A thorough review of the operating instructions
for this instrument is recommended prior to any
component replacement. Check to be sure that
cables and other test equipment are in good
working order before attempting to troubleshoot
the 620A-4 series igniter tester.
If you turn on
the AMPTEC 620A-4,
and the
display does not come on
, it may indicate the
batteries need charging, or fuse needs replacing.
If the 620A-4 exhibits problems that cannot be
eliminated by reviewing Chapters B and D, the
following guidelines have been established to
help solve the problem.
E-2-1. Localizing the Problem
Chapter D-2 discusses how to use the
Functional Test Section
of the 620A-4 Tester to
help localize the problem. The key to successful
troubleshooting is to localize the problem to a
general electronic parameter as much as possible
before trying to pin the problem down to a
specific component. Certain questions should
be asked such as "Does the problem occur on all
ranges or on a specific range only?". If the
620A-4 Tester does not come on when powered
up, did you check the front panel fuse. The
power supplies for both the current source and
the digital voltmeter electronics are also one of
the first things that should be tested.
As it is not possible to anticipate all failure
modes of the 620A-4 series igniter tester,
servicing personnel should become familiar with
this section to gain a complete understanding of
the internal workings of the ohmmeter.
E-2-2. Component Replacement
If the malfunction is a faulty component, the
accuracy of the 620A-4 series igniter tester can
be maintained only if the 620A-4 is re-
calibrated following the component replacement
and the following precautions are taken:
Use only the specified component or its exact
equivalent. Spare parts can be ordered from
your nearest AMPTEC RESEARCH Service
Center or directly from the factory by referring
to the AMPTEC Stock Number listed in the
Parts Lists section at the back of this manual.
The highest quality 63/37 grade rosin core
electronic grade solder with a 50W or lower
maximum power soldering iron should be used.
Never use an acid core solder as corrosion of
components leads and PCB etch loss can occur.
