Intercom; Vhf Radio Operations; Transponder - Cessna 152 Training Manual

Where two radios are fitter, it is considered best practice to use COM 1 for the
primary active frequency and COM 2 for any auxiliary frequencies when
required (such as TIBA, ATIS, or listening ahead to the next frequency), to
avoid selection errors.

Intercom

The intercom sometimes incorporated in the audio select panel contains at
least a volume and squelch control. The volume control is for crew volume and
squelch for intensity of crew voice activation.

VHF Radio Operations

Once the audio panel has been set, the crew communication established, if
required, and the radio switched on, correct operation should be confirmed
prior to transmitting. All VHF radio installations will have a squelch selection to
check volume and for increased reception when required. This is either in the
form of a pull to test button or a rheostat, turned, until activation is heard.
Thereafter initial contact should be established if on a manned frequency. Most
modern radio installations have an indicator to confirm the transmit button is
active. This should be monitored on the first transmission and frequently
during initiating radio transmission thereafter.

Transponder

Wherever installed transponders should be switched to standby after start to
allow for warm up time. When entering an active runway for departure, until
leaving the active runway at the end of the flight, the selector should be in ALT
if available or ON.
Many commercial
transponder equipped targets for traffic separation purposes.
The following international transponder codes are useful to remember:
Where no code is specified
Emergencies
Radio failure
by D. Bruckert & O. Roud © 2004
CESSNA 152
aircraft now contain
2000
7700
7600
TRAINING MANUAL
TCAS and can observe other
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