Control And Supply Voltages; Power; Supply Voltages - Codan X-2 Service Manual

Technical Description 4-2

4.1 Control and Supply Voltages

All switching, except power on, is controlled either directly or indirectly by
the microcontroller located on the Rx/Exciter PCB.
4.1.1

Power

104-02909
When contact S1
closed,
interconnecting cables between the Front panel, Rx/Exciter, and the PA
assembly. K8 relay energises and closes contacts K8-1
supply to the Transceiver.
Diode D5 in series with K8 prevents the relay from energising should the
supply be accidentally connected in reverse.
4.1.2

Supply Voltages

The supply voltages used on the Rx/Exciter PCB are shown in Table 4.2.
Supply
'A' rail
'B' rail
+5VA
+5VB
Table 4.2: Rx/Exciter PCB Supply Voltages
The supply voltages used on the PA PCB are shown in Table 4.3.
Supply
'A' rail
+5V
+5V
Table 4.3: PA PCB Supply Voltages
[D2] (part of volume control assembly) on the front panel is
a ground is applied to relay K8
[104-02908]
Description
unregulated battery supply
+10 V regulated supply
5 V regulated supply
5 V regulated supply
Description
unregulated battery supply
5 V regulated supply selected in transmit only
5 V supply to IC1
X-2 Technical Service Manual
on the PA assembly via
[C10]
, applying the DC
[D11]
Regulator
IC401
IC3
IC402
Regulator
IC2
V1
Publication No: 15-02047