TM 55-4920-390-13&P
6-4. RESISTANCE CHECKS.
Before applying 28
VDC power to
Strobex, perform the resistance checks as
shown in
Table 6-2. Use voltohmmeter. DO NOT apply 28 VDC power to Strobex.
From
To
Resistance Readings
+ Meter Leads)
-
Test Point 3
Ground
1
MEGOHM
Test Point A
Ground
1.1
MEGOHM
(Discharge capacitors
C101, 102 & 103)
Test Point 1
Ground
200
OHMS
(Emitter of Q1)
Test Point 2
Ground
1
MEGOHM
(Anode of SCR)
Collector of Q1
Heat Sink
200
OHMS
(center stud) (ground when
mounted in case.)
WARNING
High voltages are present in the Strobex. They may be dangerous to life, and destructive to the
instrument. Use care to avoid personal contact and avoid shorting circuit board parts. Discharge
the discharge capacitors (Test point A-to ground), whenever probing in instrument without power
applied.
The flash tube is pressurized and subject to explosion, and when operating it emits harmful ultra-
violet radiation. ALWAYS wear protective glasses when working with it and avoid looking directly
at source while it is flashing.
6-4