Amptec Research 620A 4R, Operation And Maintenance Manual

CHAPTER E    GENERAL OPERATION AND DESIGN

E-1.

General

The AMPTEC RESEARCH 620A-4R 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 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 Tester and it’s 
customer service department can also provide 
additional assistance in the trouble shooting 
process. 

E-2.

Troubleshooting

Since the 620A 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 
Tester should not even attempt to remove the 
calibration access screws or open the main 
panel or effect any repair whatsoever

. 

Apparent 620A 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 series igniter tester .

If you turn on

 the AMPTEC 620A-4R, 

and the

display does not come on

, it may indicate the 

batteries need charging, or fuse needs replacing.

If the 620A-4R 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 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 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 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 series igniter tester can be 
maintained only if the 620A 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.