GENERAL AEROSPACE
Boeing 737-300
MAINTENANCE MANUAL
EFFECTIVITY
PW245
34-53-00GA
DRAWING # GA-BC17-ATC-MM
Page 505
Use and disclosure shall be in accordance with the proprietary legend located on the cover of this document
AUG 15/10
NOTE:
To make sure the dynamic range is
≥
20dB, a diversity test must be run at a distance of less
than 50 feet (15.2 meters) from the airplane antenna.
(27)
Do a check of the MTL DIFFERENCE TEST.
(a)
Make sure the Minimum Threshold Level (MTL) difference between mode A and mode C is e
1.0dBm.
(28)
Push the PWR TEST key on the test set.
(29)
Use the SELECT key on the test set and select the bottom antenna.
NOTE
: Make sure the top ATC antenna is not in the line of sight of the test set antenna during the
POWER TEST.
(30)
Push the antenna push button switch.
(31)
Slowly move the test set antenna 3 feet vertically from the ground, at less than 1 FT/SEC (30
CM/SEC).
(32)
Push the antenna push button switch a second time to stop the test when the test set antenna is
approximately 6 feet high.
(33)
Do a check of the POWER TEST.
(a)
Make sure the peak power output of the transponder is between 125W (ERP = 51.0 dBm) and
500W (ERP = 57.0 dBm).
NOTE:
Effective Radiated Power (ERP) is the product of the antenna output power and antenna
gain.
(b)
Make sure the Minimum Threshold Level (MTL) sensitivity is -74dBm (±3dBm).
NOTE
: An additional 3dBm loss is allowed to compensate for antenna coupling errors. Also,
make sure to correct for other factors that would change the sensitivity measurement.
(c)
Make sure the test set shows PASSED for the BOT AVG (dBm).
(34)
Insert the antenna shield over the bottom ATC antenna.
(35)
Move the test set so that it is in the line of sight of the top ATC antenna.
(36)
Push the SETUP key on the test set.
(a)
Enter the appropriate range for the top antenna.
(b)
Choose the top antenna on the SELECTED field.
(37)
Push the PWR TEST key on the test set.
(38)
Use the SELECT key on the test set and select the top antenna.
(39)
Do a check of the POWER TEST.
(a)
Make sure the peak power output of the transponder is between 125W (ERP = 51.0 dBm) and
500W (ERP = 57.0 dBm).
NOTE:
Effective Radiated Power (ERP) is the product of the antenna output power and antenna
gain.
(b)
Make sure the Minimum Threshold Level (MTL) sensitivity is -74dBm (±3dBm).
NOTE
: An additional 3dBm loss is allowed to compensate for antenna coupling errors. Also,
make sure to correct for other factors that would change the sensitivity measurement.
(c)
Make sure the test set shows PASSED for the TOP AVG (dBm).
