TM 55-1520-240-T
5-2.5 PHAZOR CLOCK ANGLE INDICATOR LIGHTS DO NOT
COME ON (Continued)
DISCONNECT PLUG FROM RO-
TOR BLADE RECEPTACLE
138J1. CHECK FOR 28 VDC
BETWEEN ROTOR BLADE
RECEPTACLE 138J1, PIN P (+)
AND GROUND. IS 28 VDC
PRESENT?
TO 0.025 INCH?
LOCATE OPEN IN WIRES W673-
39-20, W639-17-22, OR W552-
7-22 BETWEEN BLADE
TRACK RECEPTACLE 138J1
AND BLADE TRACK
CB138CB1. REPAIR OR RE-
PLACE WIRE AS REQUIRED.
CHECK FOR GROUND ON RO
TOR BLADE RECEPTACLE
138J1. PINS N AND M. IS
GROUND PRESENT?
LOCATE OPEN IN WIRE W673-
GD134A20N OR W673-
GD307A20N BETWEEN BLADE
TRACK RECEPTACLE 138J1,
PIN N AND M AND FUSELAGE
GROUND. REPAIR OR REPLACE
WIRE AS REQUIRED.
CHECK GAP BETWEEN MAG-
NETIC PHASE DETECTOR AND
INTERRUPTERS. IS GAP 0.015
ADJUST GAP. REFER TO TM 55-
1520-240-23.
CHECK RESISTANCE ON BLADE
TRACK RECEPTACLE 138J1
BETWEEN PINS E AND A, 8, C,
OR D. IS RESISTANCE 900 TO
1100 OHMS PRESENT?
CHECK CONTINUITY BETWEEN
MAGNETIC PHASE DETECTOR
PLUG 138P3, PIN 8 AND
BLADE TRACK RECEPTACLE
138J1, PIN E. IS CONTINUITY
PRESENT?
LOCATE OPEN ON WIRES
W639-19-20 BLU OR W673-38-
22 BLU BETWEEN MAGNETIC
PHASE DETECTOR PLUG
138P3. AND BLADE TRACK
RECEPTACLE 138J1 REPAIR
OR REPLACE WIRE AS RE-
QUIRED.
SET STROBEX MODE SELEC-
TOR SW TO A PASS A STEEL
SCREWDRIVER BLADE BACK
AND FORTH ACROSS THE
MAGNETIC PHASE DETECTOR
BETWEEN 0.020 TO 0.050
INCHES OVER POLE PIECE.
DOES FLASH TUBE FLASH?
REPLACE MAGNETIC PHASE
DETECTOR.
LOCATE OPEN IN WIRES W639-
18-20 RED, W673-37-22 RED,
W673-171-22, W673-172-22,
W673-173-22, W673-174-22,
OR W673-175-22 BETWEEN
MAGNETIC PHASE DETECTOR
5-2.5
TROUBLESHOOT BALANCER
(TM 55-4920-402-13&P).
END OF TASK
5-11
