34-53-00
(1) The system test is a complete system checkout of the ATC. The first part of the system test consists of the performance of all tests possible using only the built-in test capability of the equipment installed in the airplane (operational test). The balance of the system test requires the use of an ATC ramp test set.
B. Equipment and Materials
(1)
Transponder/DME Test Set, IFR Model ATC-600A
(2)
Portable pressure equipment to simulate 0 to 35,000 feet altitude and 0 to 400 knots airspeed.
C. Referenced Procedures
(1)
AMM 34-11-00 Adjustment/Test
(2)
AMM 34-12-00, Adjustment/Test
(3)
AMM 34-53-00, Adjustment/Test (Operational Test)
D. Prepare to test ATC system
NOTE: The test set is a source of interference for radio and L-band
____ radar equipment operating on airplanes located in the vicinity of the test set. Turn test set off as soon as the test is completed or when other radio checks are being performed on the airplane.
(1) Position remote test set antenna approximately 21 inches from ATC antenna for system under test. Test set antenna should be approximately same height as the airplane antenna.
CAUTION: NEVER PLACE REMOTE TEST SET ANTENNA CLOSER THAN 15 INCHES
_______ TO THE AIRCRAFT ANTENNA WITH TEST SET"ON". DAMAGE TO THE TEST SET WILL RESULT.
(2)
Route and connect coax from remote test set antenna to Test set.
(3)
Position controls on test set as follows:
PWR Switch OFF Mode Switch A/C Code SLS Switch Center position Framing Control 0 INTERR Control 0 XPDR SIG Control FULLY CCW XMTR FREQ Control 0
CAUTION: IN THE FOLLOWING TESTS DO NOT SELECT CODES 7500,
_______ 7600, OR 7700. THESE ARE EMERGENCY CODES.
NOTE: In the following tests the reply light on the ATC control
____ panel shall illuminate whenever the ATC transponder transmits a reply to the test set, unless otherwise stated. Also the % reply meter on the test set shall indicate 100% when the transponder is replying (unless specified otherwise).
EFFECTIVITY AF ALI ALL; DLH ALL; IBE ALL;
AF SAB ALL; AF, AT,MD, GN, AF AND VM WITHOUT AEB 34-587 CONFIG 1 AF AND 34-607 02 A Page 509
Oct 25/96
34-53-00
(4) Close ATC System and Altitude Source (ALTIMETER or CADC) circuit breakers.
E. Test ATC System
(1)
Activate ATC system to be tested in Mode A with ALT RPTG off and code 0000 selected.
(2)
Perform ATC system OPERATIONAL TEST paragraph 2, 34-53-00, ATC system - Adjustment/Test.
(3)
Place PWR switch on test set to AC or BAT as appropriate. Test set display shall indicate 0000.
NOTE: For information regarding battery testing, timing and
____ recharging refer to operation section of ATC-600A test set operators manual.
(4)
Test receiver sensitivity as follows:
(a)
On test set, verify % REPLY meter indicates 100.
(b)
Slowly rotate XPDR SIG control clockwise until % REPLY meter indicates 90. The XPDR SIG control shall be between 69 and 77 (Note control reading. This is transponder system minimum triggering level).
(c)
Select ALT RPTG on ATC control panel and A/C ALT on test set.
(d)
Repeat step (b). XPDR SIG control reading shall not differ from reading in step (b) by more than 1.
(e)
Return XPDR SIG control fully counter clockwise. Position test set mode switch to A/C CODE.
(5)
Test Side Lobe Suppression as follows:
(a) Adjust the XPDR SIG control on test set to 3 db above minimum triggering level.
NOTE: If the transponder's sensitivity is near the insensitive
____ limit, it may be necessary to move antennas closer together in order to get 3 db above minimum triggering level. At closer than normal antenna spacing, re-establish the dial setting for MTL and adjust the dial 3 db above MTL and make the SLS test.
(b)
Position SLS switch on test set to 0 db. Transponder shall stop all replies.
(c)
Position SLS switch on test panel to -9 db. Transponder shall reply to at least 90% (minimum) to 100% as indicated on test set % REPLY meter.
