Specifications

7
USER STATION CONNECTIONS
Routing the TW Intercom System cables along the same
ductways and pathways as power cabling can increase the
noise and hum levels.
Moisture / Contamination Protection
When using equipment in the rain, always protect the equip-
ment with plastic covers----also, make sure all cable con-
nectors are lifted out of the mud or snow and protected with
plastic bags. Water, mud and snow in connectors can cause
considerable audible noise.
Hum Prevention
Prevent inducing hum into the system by not locating user
stations near hum sources such as power transformers, elec-
trical switch panels, lamp dimmers or TV cameras. When the
microphone switch is turned on, the dynamic microphone
acts as a sensitive antenna for hum sources.
USER STATION CONNECTIONS
Dynamic Microphone headset connector:
XLR-4-31 type receptacle (J1)
Input level: -55 dbu nominal
Output level to headphone: 10 volts peak-to-peak open
circuit.
Pin 1 - Microphone low
Pin 2 - Microphone high
Pin 3 - Headphone low
Pin 4 - Headphone high
Carbon Microphone headset connector:
Standard 1/4" Phone Jack (J2)
Input level: -15 dbu nominal
Output to Headphone: 10 volts peak-to-peak open circuit.
Tip - Carbon Microphone
Ring - Headphone
Sleeve - Common/ground
Line input connectors: (J3/J4)
XLR-3-31/32 types (for two-channels)
Pin 1 - Common (low side of line)
Pin 2 - Channel 1
Pin 3 - Channel 2
XLR-4-31/32 types (for three-Channels)
Pin 1 - Channel 1
Pin 2 - Channel 2
Pin 3 - Channel 3
Pin 4 - Common (low side of line)