TM 11-6625-820-45
check for continuity and to check the
spection of the wiring and connec-
value of resistance in a circuit. For
tions.
these checks, use Multimeter ME-26
(4) Resistor color code. The resistor color
(*) /U, or equivalent.
code diagram (fig. 48) is provided
to aid maintenance personnel in deter-
Caution: Be sure that the multim-
mining the value and tolerance of re-
eter is not placed across a meter in
sistors.
the test set. The current from the
ohmmeter might damage the micro-
2-3. Test Equipment Required
ampere movement of a meter of the
The following chart lists equipment required
test set.
for troubleshooting Test Set, Radio AN/ARM-
(2) Voltage m e a s u r e m e n t s . V o l t a g e
92 or AN/ARM-92A. It also lists the assoc-
measurements are used to check to
iated technical manuals.
see if the proper amount of voltage is
a. Make test equipment connections with
being routed through the test set and
care so that shorts will not be caused by ex-
aid box. For these measurements, use
p o s e d test equipment connectors. Tape or
Multimeter ME26(*)/U, or equiva-
sleeve (spaghetti) test prods or clips as neces-
lent.
sary to leave as little exposed metal as need-
In all these
(3) Intermittent troubles.
ed to make contact to the circuit under test.
tests, the possibility of intermittent
b. Observe polarity; a negative ground is re-
troubles should not be overlooked. If
quired on the 27.5-volt dc line. The low side
present, this type of trouble may often
of the ac line is also grounded.
be made to appear by tapping or jar-
c. The following test equipment is required:
ing the equipment. Make a visual in-
Common name
Technical manual
Test Equipment
TM 11-6625-588-15
Vor modulator
Modulator MD-83A/ARN
Output meter
TM 11-5017
Output Meter TS-585(*)/Ua
Multimeter
TM 11-6625-200-12
Multimeter ME-26(*)/Ub
TM 11-6625-535-15
Oscilloscope AN/USM-140A
TM 11-6625-320-12
Vtvm
Voltmeter, Meter ME-30A/U and Voltmeters,
Electronic ME-30(*)/Uc
TM 11-6625-492-12
Resolver test set
Test Set, Resolver AN/ASM-101
Indicator test set
Test Set, Indicator Course AN/ASM-110
TM 11-2535B
Meter calibrator
Meter Test Set TS-682A/GSM-l
Resolver bridge
Bridge, Resolver, Gertsch model RB-4C-4R;
Singer Company, Los Angeles, California
a Indicates Output Meters TS-585A/U, TS-585B/U, TS-585C/U, and Audio Level Meter TS-585D/U.
b Indicates Multimeter ME-26A/U, ME-26B/U, and ME-26C/U.
c Indicates Voltmeter, Meter ME-30A/U and Voltmeters, Electronic ME-30B/U and ME-30C/U.
Section Il. TROUBLESHOOTING
PROCEDURES
2 - 4 . General
2-5. Troubleshooting Aid Box
The troubleshooting procedures are divided
into two parts. The first part (paras 25 and
Because of the simplicity of the aid box
cir-
2-6) gives procedures to troubleshoot the aid
cuitry, any trouble may be quickly isolated
by
the following checks:
box. The second part (paras 2-7 through 2-9)
a. Remove the bottom of the aid box by
re-
gives procedures to troubleshoot the control
moving the six screws on the bottom of the
aid
u n i t , the RMI the OBS indicator, and the
box.
test set.
2 - 2 Change 2
