TM 11-6625-596-45
CHAPTER 3
TROUBLESHOOTING
d. If organizational maintenance personnel
3-1.
General Instructions
have localized the trouble by following the daily
preventive maintenance and the trouble-shooting chart,
a. Several features of the TS-716/U make
the GS or depot repairman may begin at that step.
conventional troubleshooting techniques undesirable.
Otherwise, he should begin at the first step and perform
Among these features are:
each step in succession. The steps are arranged to
(1) A complex switching arrangement
quickly eliminate large portions of the test set as a
which simplifies operation but complicates troubleshoot-
possible source of trouble. Skipping steps will leave
ing.
portions of the test set untested.
(2) The use of printed circuit modules for
e. This equipment is transistorized. Observe
most of the electronic circuitry enables the substitution
all precautions given to prevent transistor damage.
of a module that is known to be good for one which is
suspected of being faulty.
equipment only as specified.
When measuring
(3) The use of highly reliable transis-
voltages, use tape or sleeving to insulate the entire test
torized circuits, which means that most failures will more
prod, except the extreme tip. A momentary short circuit
likely be due to failures of wiring and switches, rather
can ruin a transistor. Use re-sistor and capacitor color
than the failure of electronic components.
codes (FIG. 6-7) to find the value of components not
b. The first step in servicing a defective TS-
otherwise marked. Use voltage and resistance charts in
716/U is to localize the fault, which means tracing the
fault to a defective stage, assembly, or circuit, based on
and compare the normal readings with the readings
abnormal indications. The second step is isolation,
obtained.
which means locating the defective part or parts.
(1) Visual inspection.
Some defective
f.
In all tests, the possibility of intermittent
parts may be located by sight, smell, or hearing. Burned
troubles should not be overlooked. If present, this type
of trouble often may be made to appear by tapping or
nonbuzzing of 20-Hertz inverter 1A3A11 may be located
jarring the equipment.
Check the wiring and
by the senses. The meter reading should be observed
connections to, and within, the test set.
and an attempt made to localize the fault.
(2) Operational tests. Operational tests
3-2.
Test Equipment Required
frequently indicate the location of trouble. The daily
maintenance service and inspection chart (TM 11-6625-
The following chart lists test equipment required for
596-12) contains operational tests.
troubleshooting the TS/716/U.
Also listed are the
associated technical manuals and the assigned common
3b is
based upon the daily preventive maintenance
names.
checks and services chart and the troubleshooting chart
testing, short-circuit test and signal substitution
techniques are all used in the order most suitable for
locating trouble at a particular step in the checklist.
Test equipment
Technical manual
Common name
Multimeter AN/URM-105 with Multi- ----------------------- TM 11-6625-203-12 ----------------------------------------- Voltohmmeter.
meter ME-77/U.
Signal Generator TS-382/U ---------------------------------- TM 11-6625-261-12 ----------------------------------------- Audio oscillator.
Multimeter TS-352B/U ---------------------------------------- TM 11-6625-366-15 ----------------------------------------- Multimeter.
3-1