Cessna 152 - Page 231

PILOT'S OPERA TING HANDBOOK.
SUPPLEMENT
CESSNA 400 TRANSPONDER
AND ENCODING ALTIMETER
1. FUNCTION SWITCH - Controls application of power and selects transponder
operating mode as follows:
OFF - Turns set off.
SBY -
Turns set on for equipment warm-up or standby power.
ON - Turns set on and enables transponder to transmit Mode A (aircraft
identification) reply pulses.
ALT - Turns set on and enables transponder to transmit either Mode A
(aircraft identification) reply pulses or Mode C (altitude reporting)
pulses selected automatically by the interrogating signal.
2. REPLY LAMP - Lamp flashes to indicate transmission of reply pulses; glows
steadily to indicate transmission of IDENT pulse or satisfactory self-test
operation. (Reply Lamp will also glow steadily during initial warm-up period.)
3. !DENT (ID) SWITCH - When depressed, selects special pulse identifier to be
transmitted with transponder reply to effect immediate identification of air-
craft on ground controller's display. (Reply Lamp will glow steadily during
duration of IDENT pulse transmission. )
4. DIMMER
(DIM) CONTROL - Allows pilot to control brilliance of Reply Lamp.
5. SELF-TEST (TEST) SWITCH - When depressed, causes transponder to gen-
erate a self-interrogating signal to provide a check of transponder operation.
(Reply L;unp will glow steadily to verify self test operation.)
6. REPLY-CODE SELECTOR SWITCHES (4) - Select assigned Mode A Reply
Code.
7. REPLY-CODE INDICATORS
(4) - Display selected Mode A Reply Code.
8. 1000-FOOT
DRUM TYPE INDICATOR - Provides digital altitude readout
in 1000-foot increments between -1000 feet and +35, 000 feet. When alti-
tude is below 10,000 feet, a diagonally striped flag appears in the
10, 000-foot window.
9. OFF INDICATOR WARNING FLAG - Flag appears across altitude readout
when power Is removed from altimeter to indicate that readout is not reliable.
10. 100-FOOT DRUM TYPE INDICATOR - Provides digital altitude readout in
100-foot increments between O feet and 1000 feet.
11.
20-FOOT INDICATOR NEEDLE - Indicates altitude In 20-foot increments
between O feet and 1000 feet.
12.
ALTIMETER SETTING SCALE - DRUM·TYPE - Indicates selected alti-
meter setting in the range of 27. 9 to 31. 0 inches of mercury on the stan-
dard altimeter or 950 to 1050 millibars on the optional altimeter.
13. ALTIMETER SETTING KNOB - Dials in desired altimeter setting in the
range of 27. 9 to 31. 0 inches of mercury on standard altimeter or 950 to
1050 millibars on the optional altimeter.
Figure 1. Cessna 400 Transponder and Encoding Altimeter
Operating Controls (Sheet 2 of 2)
1 July 1978 3