User manual

Page 74

Aircraft Operation Manual

Piper Cheyenne I, IA, II, IIXL

For ight simulation use only

IDT

Button

Altitude

Window

Indicator

Code

Window

CLR

Button

Code Entry

Buttons

VFR

Button

Function

Selector

Knob

KT 76C Panel-mounted Transponder Operation

About Transponders

Your Honeywell Bendix/King transponder is a radio transmitter and receiver

which operates on radar frequencies. Receiving ground radar interrogations at

1030 MHz, it returns a coded response of pulses to groundbased radar on a fre-

quency of 1090 MHz.

As with other Mode A/Mode C transponders, the KT 76C replies with any one of

4,096 codes, which differ in the position and number of pulses transmitted. By

„replying” to ground transmissions, your KT 76C enables ATC computers to dis-

play aircraft identication, altitude and ground speed on Enroute, Approach or

Departure Control radar screens. When the IDENT button is pressed, your aircraft

will be positively identied to the Air Trafc Controller.

Operating the KT 76C

Before starting your aircraft’s engine, make sure that the KT 76C function selec-

tor knob, or your avionics master, is turned to OFF. After engine start, turn the

function selector knob to SBY (standby). Give your transponder about 45 seconds

to become operational. Select the proper reply code by pressing the desired code

entry buttons. The reply code will be displayed in the code window. Before ta-

keoff, rotate the function selector knob to the ALT (altitude) position for Mode

C altitude reporting to ATC. If you do not have an encoding altimeter, rotate the

function switch to ON for Mode A reporting.