TM 55-4920-390-13&P
g) If lamp does not flash, remove power and check signal cable and its connector for continuity from Pin A in
connector to Test Point C on circuit board and Pin B in connector to Test Point B on circuit board. Perform
visual inspection for obvious faults on the circuit board.
CAUTION
Dangerous voltages are present. Discharge the discharge capacitors (Test Point A to ground)
whenever working on the Strobex without power.
h) Re-apply 28 VDC and pull trigger. If light still fails to operate, remove external oscillator signal and go thru
voltage checks in Table 6-3.
NOTE
Apply 28 VDC power, but NO signal to unit for these checks. Turn "Vernier" control on rear of
hand-held lamp full CCW to turn "oscillator off".
TABLE 6-3. VOLTAGE CHECK CHART
From
To
+ Meter Leads
-
Voltage (10%)
Test Point 3
Ground
+ 230 VDC
Test Point 2
Ground
+ 420 VDC
Discharge capacitors
Ground
+ 420 VDC
(Test Point A )
Collector of Q 1 (D) Ground
+ 13 VDC
(Test Point D )
NOTE
These voltages are approximate and intended as guides for trouble shooting only.
i) To check internal oscillator, remove external oscillator signal, apply 28 VDC power, set "Vernier" on rear of hand-
held lamp to mid-range (oscillator on), set "Multi-turn Dial" to 350, and depress trigger. Light should flash at
about 30 flashes per second.
6-6
