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m4a5a_v320_eng (14.02.2013)
- 30 -
Kompetent für Elektroniksysteme
m4a5a_v320_eng (14.02.2013)
- 31 -
Kompetent für Elektroniksysteme
PWR
operating voltage 12V, max. 1,5 A
inside: positive terminal, outside: GND
Rearview Major 4a/5a
Pinout I/O
Digital In/Outputs (ST3)
IN/OUT 0
1
IN/OUT 1
2
IN/OUT 2
3
IN/OUT 3
4
IN/OUT 4
5
IN/OUT 5
6
IN/OUT 6
7
GND
8
Pinout RS232
(ST4)
NC
1
NC
2
TxD
3
RxD
4
GND
5
NC
6
Pinout S/E
Radio Circuit (ST1)
AF input B
1
AF input A
2
Squelch input
3
GND
4
12 V, max. 200 mA
5
PTT active, low
6
AF output A
7
AF output B
8
Pinout PTT
Headset (ST2)
GND
1
GND AF input (mic. -)
2
NF earphone
3
GND earphone
4
AF input (mic. +)
5
PTT, active GND
6
Sockets Pinout Major 4a/5a
All AF in/outputs are equipped with transformers
and, hence, potential-free. PIN 5 is for supply
(+12V) of external devices (LIM-AC, FT634C).
Attention:
Do not use PIN 5 to supply a radio
set. 200 mA output current is not sufficient.
There are two sockets for connecting a headset.
One is for connecting the headset, the other
for the use of an external PTT button (e.g. foot
switch)
The digital connections can be configured as
inputs or outputs, respectively. Usually, these are
used as outputs for remote channel select.
To socket RS232 a printer can be connected.
All of the schemes show the sockets as viewed from the rear of the Major.
ST1
ST2A
ST4
ST2
ST3
PWR
Pinout HS
Headset (ST2A)
GND
1
AF input (mic. +)
2
AF earphone
3
GND earphone
4
GND AF input (mic. -)
5
PTT, active GND
6