Service manual

3VX-4500/-4600 Series UHF FM Transceiver Service Manual
DSUB 15-pin Accessory Connector
Pin 1: AF IN
(
ANALOG INPUT
)
External Microphone Input. Nominal input level is
4 mV (or –10 dBm; programmed via the CE115 program-
mer) at 600-ohm.
Pin 2: AF OUT
(
ANALOG OUTPUT
)
Low-level receiver output. Peak signal level is –10 dBm at
600-ohm.
Pin 3: AF GND
Ground for all logic levels and power supply return.
Pin 4: DC OUT
(
13.6 V DC OUTPUT
)
Switched 13.6V output for supplying power to an acces-
sory.
Maximum output current is 1 A.
Pin 5: RSSI
(
ANALOG OUTPUT
)
A DC voltage proportional to the strength of the signal cur-
rently being received (Receiver Signal Strength Indicator)
is provided on this pin. This low impedance output is
gererated by the receiver IF sub-system and bufferd by an
internal op-amp. Typical output voltages are 1 V (@No Sig-
nal Input) through 2.5 V (@50 dB Signal Input).
Pin 6: EXT PTT
Shorting this port to ground causes the transceiver to be
placed in the Transmit mode, while opening the connection
to this port returns the transceiver to the Receive mode.
Opening voltage is 5 V, closed current approx. 5 mA.
Pin 7: TRX
This port is intended for controlling an external TX/RX
switching circuit. When the transceiver is placed in the Re-
ceiver mode, this port is 5 V. When the transceiver is placed
in the Transmit mode, this port reduce to 0 V.
This port is open drain output which can sink approx. 50
mA when active.
Pin 8: ING
(
IGNITION SENSE FEATURE
)
The VX-4500/-4600 may be automatically be switched to
the STND-BY mode when the vehicle’s ignition key is turned
on. Maximum current is 20 mA.
Pin 9 - 12: ACC1 - ACC4 (ACCESSORY PORT)
These port features can be programmed via the CE115 pro-
grammer. Each port is open drain output which can sink
approx. 50 mA when active. Max. output 16 V.
When the input is selected, it becomes active between 2 V
and 16 V.
Pin 13: ACC5 (ACCESSORY PORT)
The port 5 is available to set only for Output function, and
active logic is opposite side against the Port 1 ~ 4.
Max. output 5 V, closed current approx. 1 mA (CMOS out-
put).
Pin 14: ACC6 (ACCESSORY PORT)
The port 6 is available to set only for Input function, and
active logic is opposite side against the Port 1 ~ 4.
Max. input 5 V (CMOS input).
Pin 15: GND
Chassis ground