ENC-3300-DTMF
Carrier Detect
Carrier detect is used to signal the ENC-3300 to wait until the channel is clear of traffic.
Connector J3 has an input labeled “
/CD
” which interfaces with the channel busy indicator from the
radio.
The
/CD
input is “active low”. This means the two-way radio needs to supply a ground (low) output
when the channel is busy and it doesn't want the encoder to transmit.
When the channel is available the radio can release its low output and float up to 12 volts dc. The
ENC-3300 waits one second extra after the
/CD
line goes high before beginning any pending
transmissions.
The J3 connection labeled “GND” is normally connected to your radio's signal ground so the encoder
and the radio have a common ground level to compare. Many times GND can simply be connected to
the radio's power supply ground.
See CDWAIT – Carrier Detect wait time in seconds on page 36 for additional information on asjusting
the maximum wait time.
See PRIORITY on page 40 for information on different methods to interact with carrier detect on an
individual button level.
Genave/NRC,Inc. 9000-0000-086 rev 4
Pg. 27