User's Manual
14221-1200-4010, Rev. B
73
Table 13-1: Option Cable 14002-0174-01 Interconnections
44-PIN I/O
CABLE
CONNECTOR
P1 PIN
SIGNAL NAME
TO/FROM
DESCRIPTION
5
FDISC
P4 pin 9
Buffered Filtered Discriminator Audio Output (not
normally used). A fixed-level audio output with DC bias.
Approximately 200 mVrms into a 600-ohm load at rated
deviation. Does not contain signaling (e.g., CTCSS).
Mutes when speaker mutes. Use a 33 µF / 50 V (or
greater) coupling capacitor to connect to a 600-ohm load.
Use P4 pin 12 for ground.
13
ALO
P4 pin 10
In a remote-mount radio installation, these two pins of the
radio’s DB-44 connector are not functional.
12
MICHI
P4 pin 11
1
EXTALO
P4 pin 12
VOLHI (a single-ended AC-coupled audio signal) and
EXTALO (signal ground) provide an unmuted volume-
level-controlled single-ended receive audio signal to
external devices. P1 pin 1 (EXTALO) is over-current
protected inside the radio by a 1-amp fuse.
14
VOLHI
P4 pin 13
15
CTLON
P4 pin 14
Control-On Digital Input. Logically OR’d inside radio with
a CAN receiver activity logic signal, so either input can
turn on the radio. Not normally used.
16
XTONEENC
P4 pin 15
External Tone Encode Audio Input (default) or Auxiliary
Mic Audio Input.
17
XTONEDEC
P4 pin 16
External Tone Decode Audio Output.
6
EXTALO
P4 pin 17
Reference/Ground for external audio. Over-current-
protected inside the radio by a 1-amp fuse.
24
HORNRING
P4 pin 18
For a remote-mount radio installation, see footnote
2
.
23
SONOFF
P4 pin 19
For a remote-mount radio installation, see footnote
2
.
18
INP1
P4 pin 21
Digital Input 1. Active = Ground. Inactive = Open. Use P4
pin 1 for ground.
Configure via the “Auxiliary Input 1” in Radio Personality
Manager’s (RPM’s) External I/O dialog Box.
2
OUT1
P4 pin 22
Digital Output 1 (open-collector, 100 mA / 17 V maxi-
mum). An external pull-up resistor is needed if required
by the external device’s input during the high/off state.
Use P4 pin 1 for ground.
Configure via the “External Output Control Line 1” in
Radio Personality Manager’s (RPM’s) External I/O dialog
Box.
29
TXENB+
P4 pin 23
Transmit Enable B+ Output (open-collector). Active/Radio
Transmitting = Ground. Inactive/Not Transmitting = Open
(not normally used).