Crown OC-150A - Troubleshooting Common Issues

* Unit doesn't turn on (as
indicated by meteys and
pilot light],
2. Braken, cracked meter,
3, Internittent function
buttoas *
4. Internittent &@adphone
attenuator slide switch,
5, e%i.ttery or
sn m@ters,
6. Hold circuit nst.
CkUSE
I
I 1, a, BPam fuse
b. D6, 07; C5, C6 faulty.
e. Faulty trawsformer,
2. a. Unit exposcd to freezing
temperature,
b. U~i.it handled carelessly in
shipment,
c. Meter mount screws tightened
excessively.
3, a, Dirty switch contacts,
b, Faulty switch,
4, a, Dirty switch contacts,
b. Switch handle not moving
eorreetly th~ough its 3-
posit ion range *
5. a, Faulty semiconductar device
in meter circuitry (Q3,Q4,
sc-a) ,
6. a, Faulty component in hold
circuitry; (Ql, IC- l D, C49,
1, 3, Replace fuse; seek
cause,
b, Kaplsce se%pectiara
power sulaply c
c, Replace TB,
2, a, Replace me%erfca%ib~atc
be Replace meter/calib~ate
c, Replace meter; da not
3. a, Spray with st~per
contact cleaner and
work free by rapid
movement,
h, Replace switch*
4, 3, Spray with cleaner,
b. With DremcZ drill,
create slot% apposite
where they do not
presently exist (see
Fig, 1) A3so file
bigger switch hoke
slot on OC-I TOA back
panel ,
5, :%, Replace prableai
co~~pcan~nt a
6. a. Replace problem
conn~~anent,