C. Remove the aerodynamic sealant from around the marker beacon antenna base (AMM 51-31-01/701).
D. If it is necessary, remove the aerodynamic sealant found on the head of each screw.
5. Remove the Marker Beacon Antenna
________________________________
A. Support antenna and remove antenna mounting screws.
B. Break the seal around the marker beacon antenna.
CAUTION: BE CAREFUL WHEN YOU BREAK THE SEAL AROUND THE MARKER BEACON
_______ ANTENNA. TOO MUCH FORCE CAN CAUSE DAMAGE TO THE ANTENNA OR THE AIRPLANE MATING SURFACE.
C. Lower antenna until antenna cable can be disconnected.
CAUTION:_______DO NOT PULL ON THE ANTENNA CABLE. YOU CAN CAUSE DAMAGE TO THE CABLE AND THE MARKER BEACON ANTENNA.
D. Disconnect antenna cable from antenna connector and carefully remove antenna.
6. Prepare for Installation
________________________
A. Clean the faying surfaces of the airplane structure and the marker beacon antenna. If the surface is anodized, clean with a 220 or finer abrasive.
(1)
Use a clean cloth to clean the faying surfaces.
(2)
Do these two steps until the metal of the bonding surface is bright, clean and dry.
EFFECTIVITY
ALL 04 Page 401 Oct 25/9734-32-01
Marker Beacon Antenna Removal/Installation
Figure 401
EFFECTIVITY ALL
701 Page 402
34-32-01
Oct 10/73
(3) Apply a layer of alodine to the airplane and antenna mating surfaces.
7. Install the Marker Beacon Antenna_________________________________
A. Connect antenna cable to antenna.
B. Align the antenna to the screw holes in the fuselage.
C. Lightly tighten the cad plated stainless steel screws to hold the antenna in the correct position.
D. Manually tighten the screws to 15-17 pound-inches of torque.
CAUTION:_______TIGHTEN THE SCREWS MANUALLY TO THE CORRECT TORQUE VALUE. USE OF POWER OR AIR TOOLS TO TIGHTEN THE SCREWS CAN CAUSE DAMAGE TO THE ANTENNA SURFACE.
E. Do a check of the continuity between the antenna and the airplane skin:
(1)
Connect the bonding meter between the head of each screw and the airplane skin.
(2)
Make sure each measurment of continuity is less than 25 milliohms (AMM 20-22-01/601).
F. Apply the weather aerodynamic sealant, BMS 5-95, to the outer edge of the antenna (AMM 51-31-01/201).
G. Apply the weather aerodynamic sealant, BMS 5-95, to the head of each screw (AMM 51-31-01/201).
H. Remove the unwanted sealant from around the antenna base
(AMM 51-31-01/201).
I. Close circuit breaker opened in steps 4A and 4B.
8. Perform the Post Installation Test__________________________________
A. Test Marker Beacon Antenna
(1)
Set up marker beacon test generator approximately 15 feet from marker beacon antenna.
(2)
Extend test generator antenna and align parallel to fore and aft axis of airplane.
(3)
Turn on test generator and allow warmup.
(4)
Adjust marker beacon sensitivity switch to maximum sensitivity.
(5)
Set test generator for 400-Hz modulation at 75-MHz carrier frequency. Check that blue outer marker lights illuminate.
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本文鏈接地址：747飛機維護手冊AMM CHAPTER 34 - NAVIGATION 第34章導航2(56)
