Garmin GTX 320 ATC - Manual (Page 18)

190-00133-02 Rev B 3-9
5. Successively turn-on each altitude toggle switch on the test panel. ______ OK
6. Altitude coded pulses shall appear between the P1 and P3 pulses as viewed on the oscilloscope and shown in
Figure 3-4. ______ OK
7. Verify that the unit is correctly encoding the altitude by observing the XPDR CODE digital display on the
ATC-1400A when each set of altitude switches, A through D are toggled. ______ OK
Figure 3-3. P1 and P3 Pulses
Figure 3-4. Altitude-Coded Pulses