TM 11-5821-333-30
Section III. TROUBLESHOOTING
3-8. GENERAL
This section has an operational check and troubleshooting flow charts. The operational check provides a com-
plete evaluation of the rcu. If passed, the rcu can be returned to service. The troubleshooting flowcharts are
used when the rcu fails an operational check step. The troubleshooting flowcharts are used to find the bad
module.
When an rcu is received for troubleshooting, do the following:
a.
b.
c.
d.
e.
Inspect rcu for damage. Repair any damage before proceeding.
Do the operational check.
Do any troubleshooting called for by the operational check.
Replace the bad module.
Verify the repair by doing all of the operational check.
NOTE
The troubleshooting procedures are for both AN/ARC-201(V) and AN/ARC-201A(V) radio sets.
But some of the rcu keyboard markings are different. In the troubleshooting procedures, the
AN/ARC-201A(V) marking is given first, followed by the AN/ARC-201(V) marking in paren-
theses. Example: ERF/OFST (SEnd/OFST).
3-9. OPERATIONAL CHECK
The operational check is a series of steps used to evaluate rcu operation. They are used both during
troubleshooting and to verify the rcu is good after repair.
Test Description. Each step checks the response of the rcu to an operator action. The steps are numbered so
they can be used for reference on maintenance worksheets. Each step is titled according to the function being
checked.
How to Proceed. If normal results are found proceed to the next step. If abnormal results are found, replace the
indicated module or go to the indicated troubleshooting flowchart.
WARNING
Connect the test setups only when directed and with the power supply turned off. The large
current capacity of the test power supply can cause personal injury. Verify the test setup before
turning the power supply on.
CAUTION
To avoid damage to equipment, always set DC switch on test adapter to OFF before turning
power supply on.
Before setting DC switch on test adapter to ON, always set rt and rcu FUNCTION switches
to STOW or OFF. This applies to the uut, the ref rt, and the ref rcu. Failure to do so
may damage an rt or rcu.
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