TROUBLE ANALYSIS.

Calibration will be performed in the AN/TSM-55V5

mainteance calibration shelter.

instrument on the etched board (see Fl, Figure 4-2). Be sure to insert

a proper value fuse, as indicated in the parts list.

4-5. TROUBLE ANALYSIS.

4.5.1. GENERAL.

A General Radio Type 1806 Electronic Voltmeter, or any reliable

voltohmeter, can be used for most checks described in the following

paragraphs.

4.5.2 PRELIMINARY CHECKS.

If the stroboscope is inoperative, make the following simple checks

before removing the instrument from its case:

a Check that voltage is available at the power receptacle to which

the unit is connected.

b Check that the voltage and power-line frequency of the power

source agree with the data on the panel of the instrument. If conver -

sion for a different input voltage is required, refer to paragraph 4.5.3.

c Check that the range switch is not in one of the EXT INPUT

positions.

d Turn the instrument, off and turn it on again after 10 seconds.

(The thyratron may hold over if the instrument is in an EXT INPUT

position when a plug is inserted in the INPUT jack.)

Figure 4-2. Top internal view of Type 1531 Strobotac.