Clearance Delivery Radio (Cdr) - BOMBARDIER LEARJET 40 Pilot's Manual

Pilot's Manual

CLEARANCE DELIVERY RADIO (CDR)

The Clearance Delivery Radio (CDR), Figure 5-17, is located on the
right, front corner of the center pedestal. The CDR provides an alterna-
tive capability for tuning the VHF COM 1 transceiver and the VHF
NAV 1 radio. The CDR will tune the VHF COM radio prior to applying
electrical power to the airplane. The CDR control head is normally
powered by the left essential bus through the AUDIO 1 circuit breaker;
however, it and other communication related equipment can be pow-
ered from the right forward hot bus, prior to applying electrical power
to the aircraft.
With airplane batteries OFF, depressing the momentary action RADIO
CTL HOT BUS switch on the center pedestal applies power from the
right hot bus to the left audio control panel, CDR control panel, COM
section of the integrated communications unit, and NAV section of the
integrated navigation unit. The display on the CDR is liquid crystal
type with white letters on a black background. The push button,
display, and control identifier legend are on a black background
displayed with electroluminescent lighting.
In the emergency mode, RMU and FMS tuning capabilities are inhibit-
ed and the COM and NAV units are tuned exclusively by the CDR. An
AUX ON caption replaces the NB or WB annunciators on the RMUs to
indicate that tuning through the RMUs is inhibited. Tuning through the
CDR is no different when EMRG is selected, but the CDR does not look
at the radio bus data to check the echoed frequency.
5-63
PM-132A