(2)  
On test receiver set input selector to INT position and activate by turning gain control to full up.

(3)  
Temporarily short water switch, center contact on one end of ULD, to case with jumper wire.

(4)  
With tuning control set between 35 and 40 kHz, an audible pulse should be heard at approximately one second intervals. If the pulse rate deviates greatly from one per second or the signal is weak, the ULD should be replaced.

NOTE:  The ultrasonic test receiver may be checked by jingling keys or coins in front of the microphone. A change in tone should be heard in the loudspeaker.
Oct 20/84 23-71-0 Page 201
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.

H45213
Dukane Model 42A12 Ultrasonic Test Receiver  505 
23-71-0Page 202   Figure 202 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  Oct 20/84 

VOICE RECORDER SYSTEM -ADJUSTMENT/TEST
1. General
A.  The following tests will provide assurance that the voice recorder system is functioning properly and is ready for use. There are no system tests or adjustments.
2.  Operational Test - Voice Recorder System
A.  Prepare to Test
(1)  
Provide ground electrical power to airplane.

(2)  
Check that VOICE RECORDER and INTERPHONE circuit breakers on panel P6-2 are closed:

B.  Test Voice Recorder System Operation
(1)  
Plug headset into HEADSET jack on voice recorder control panel.

(2)  
Press TEST pushbutton on voice recorder control panel for at least 5 seconds. During this time, ascertain that a 600-Hz tone is present at intervals of approximately 0.8 seconds and observe that the meter needle indicates in the green area.

NOTE:  Fluctuation of the meter needle during test is normal; however, a brief dip out of the green area indicates a defective channel.

(3)  
Press ERASE pushbutton on voice recorder control panel for 2 to 3 seconds and release. Ascertain that 400-Hz tone is present for 5 to 10 seconds after pushbutton is released.

(4)  
Release parking brake, press ERASE pushbutton on voice recorder control panel and release. Ascertain that 400-Hz tone is not present after pushbutton is released.

WARNING:  BEFORE RELEASING PARKING BRAKE, VERIFY THAT WHEELS ARE CHOCKED AND CLEAR ALL PERSONNEL FROM WHEEL AREAS.

(5)  
Reset parking brake, press ERASE pushbutton for approximately 1/2 second, and ascertain that 400-Hz tone is not present after release of pushbutton.

(6)  
Speak in a normal voice in flight compartment at least 4 feet from area microphone, continue to monitor audio with headset, and ascertain that spoken audio is present after approximately 1/2-second delay.

(7)  
Cover area microphone on voice recorder control panel to prevent pickup of sound.

(8)  
Check captain's recorder channel.

(a)  
Monitor voice recorder audio.

(b)  
Select interphone at captain's audio selector panel.

(c)  
Speak into captain's microphone.

(d)  
Ascertain that spoken test message is present in recorder output audio after delay of approximately 1/2 second.

(9)  
Repeat step (8) at first officer's and first observer's stations.

(10)
Disconnect headset.

(11)
Remove electrical power if no longer needed.

535 
Feb 15/72  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  23-71-0 Page 501 

535 
23-71-0 Page 502  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  Aug 15/72 

VOICE RECORDER UNIT - REMOVAL/INSTALLATION

1.  General
A.  The voice recorder unit is mounted in the aft cargo compartment on the right side of the airplane. All electrical connections are made through a single connector at the rear of the unit.
2.  Remove Voice Recorder Unit
A.  Open VOICE RECORDER circuit breaker on circuit breaker panel P6-2.
B.  Remove voice recorder unit.
3.  Install Voice Recorder Unit
A.  Install voice recorder unit.
B.  Close VOICE RECORDER circuit breaker on circuit breaker panel P6-2.
C.  Test voice recorder unit.
(1)  
Provide ground electrical power to airplane.

(2)  
Plug headset into MONITOR jack on voice recorder unit.

(3)  
Press TEST pushbutton marked ALL for at least 5 seconds and check that 600-Hz beep is present at MONITOR jack at intervals of 0.8 second. 
　
中國航空網 m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：737 AMM 飛機維護手冊 通訊 COMMUNICATIONS(54)