Learjet 60 - Communications; VHF Communications

Pilaf's
Manual
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Leaxjet60
COMMUNICATIONS
VHF COMMUNICATIONS
Dual VHF communications transceivers and controls are installed to
provide AM voice communication capability .
Several VHF COMM packages are available :
The
transceivers are SELCAL compatible with analog
audio
interfaces .
Tuning is accomplished via
the Radio
Tuning Units (RTU) on the center
instrument
panel
or via the Control Display Units (CDU) in the pedes-
tal . Collins or UASC
CDUs have similar radio management functions
but differ on RTU failure procedures . (Refer to AFM for detailed
mal-
function information) . The design of the system, is such that all radio
management functions are channeled through the RTUs, regardless of
their origin . The left RTU
normally tunes COMM 1 and the right RTU
normally tunes COMM 2 . If an RTU fails, the
remaining RrU is capable
of tuning both COMM 1 and COMM I Power for the system is 28'VDC
supplied through the 7 .5-amp COMM 1 and COMM 2 circuit breakers
on the pilot's and copilot's circuit breaker panels . COMM 1 is powered
during EMER BUS operations
.
The above information is presented in a general manner and is intend-
ed for familiarization only . For a detailed description and operation of
the VHF communications system refer to "Collins Pro Line 4 Avionics
System For The Learjet 60" (P/N 523-0777003) .
540
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PM-123
Change 4
Available
Package Frequency Range Frequency Spacing
1 118 .00 to 135 .975 MHz 25 kHz
steps
2 118 .00 to 151 .975 MHz 25
kHz
sops
3 118 .00 to 136
.975 MHz 8 .33 kHz steps
4
118 .00 to 136 .975 MHz 8 .33 kHz ste s
137 .00 to 151 .975 MHz 25 kHz
step