SC4x0 Technical manual
Page 32 of 34
SeaCom
Rev
2.00
13.1.8 Headset
Handset is connected using 4 wires or 6 wires. 2 wires for microphone, 2 wires for speaker and 2
wires for the PTT. The PTT switch must be a potential free switch capable of operating 5Vdc.
Output power is approx. 1watt max for 8 ohm. Use 8 ohm speakers or higher in series. Microphone
may be both dynamic or electret type. Use a shielded cable and connect shield to PE (or PTT gnd).
PTT switch may be pulse or flip switch type located on the headset or separate box.
13.1.9 Cable & terminals
All terminals are 2.5mm
2
flat head crew terminals.
All cables should be shielded cables. If terminated at the telephone, termination must be made to the
‘PE’ terminal.
13.2 General environmental data
Operating
voltage
24Vdc/1.5Adc
Ambient temperature –operation:
-25 .. +70°C
Ambient temperature –storage:
-30 .. +70°C
Humidity, vibration, EMC / ESD:
IEC60945
Compass safe distance:
>7 meters.
Surface:
Water and oil resistant.
Environmental:
RoHS
compliant
13.3 I/O & signaling interface
Supply:
24Vdc
+30%/-25%,
1.5Adc
Dimmer input:
0-30, 5-24V = 0-100%, <20mA
Line voltage -idle:
20-50Vdc
Line voltage –ringing:
40-90Vrms @20-50Hz. Pure AC and AC mixed on DC.
Line impedance:
600ohm
Line signaling:
DTMF & LD (DTMF: -10dBm / 240mV @600ohm)
Ringing relay:
24-50Vdc @ 1-0.5A.
Local speaker output:
1W @ 8ohm, >85dB @ 1m
Headset speaker output:
1W @ 8ohm
External speaker output:
12W @ 8ohm, 115dB @ 1m – if speaker 96dB/W
(Speaker must be > 8ohm)
Local & handset mic.input:
Electret type.
Local microphone:
Normal operating signal range 70 – 110dB.
Headset mic.:
Electret & dynamic type,
max signal 135dB @ 2mV/Pa if dynamic type.
Loudhailer mic.:
Dynamic type.
PTT
input:
Potential
free
switch.
Hook switch input:
Potential free switch
Handset speaker
>32ohm
Headset speaker:
>8ohm 1W
