Cessna 150 STANDARD Service Manual page 247

TROUBLE
*POWER LOW
PROBABLE CAUSE
Low battery voltage.
Faulty transmitter.
Faulty co-axial
antenna cable.
REMEDY
1. Set toggle switch to off.
2. Remove plastic plug from the remote jack
and by means of a Switchcraft #750 jackplug,
connect a Simpson 260 model voltmeter and
measure voltage. If the battery-pack voltage
on the 6-cell magnesium battery pack trans-
mitter is 10.8 volts or less, and on the 4-cell
lithium battery pack transmitters is 11. 2 volts
or less, the battery pack is below specification.
3. If the battery-pack voltage meets the
specifications in step 2, the battery-pack
is O. K. If the battery is O. K., check the
transmitter as follows:
a. Remove the voltmeter.
b. By means of a switchcraft 750 jackplug
and 3 inch maximum long leads, connect a
Simpson Model 1223 ammeter to the jack.
c. Set the toggle switch to ON and observe
the ammeter current drain.
If
the current-
drain is in the 85-100 ma range, the
transmitter or the co-axial cable is faulty.
4. Check co-axial antenna cable for high
resistance joints. If this is found to be
the case, the cable should be replaced.
I
I
*This test should be carried out with the co-axial cable provided with your unit.
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