Remote Control Console
50
6.3.4 TWO WIRE MODE
In two-wire mode only the two inner pins (pins 4 and 5) of the line jack are used. These two pins handle
both transmit and receive audios. Note: The TLM is shipped from the factory in 4-wire mode. To enter 2-
wire mode the following jumper settings must be present:
Jumper Position
Description
JP10
A
2/4 wire selection
JP11
A
2/4 wire selection
JP12
B
Places the RX side in high impedance state
JP1
A
Disable TX monitor
When putting consoles in parallel the receive side always remains in the high impedance state (JP12 = B).
The transmit side follows the same settings as in 4 wire mode.
Consoles in
TLM
TLM
Individual TLM
Parallel
JP8
JP9
Output Impedance
1
B
A
600 ohms
2
A
A
1200 ohms
3
B
B
1800 ohms
4
A
B
2400 ohms
The transmit monitor is not needed in 2 wire mode as the transmit audio is already on the receive circuit. JP1
is placed in the A position to disable the TX monitor.
6.3.5 RECORDER OUTPUT
Receive audio to the recorder is taken after the notch filter and is gated so that audio will be presented to the
recorder only when valid receive audio is present. For example, transmit audio is present on the receive
circuits in a transmit condition. The gate will block any audio on the receive path from the recorder in a
Transmit condition.
Transmit audio may be recorded in two states – with or without tones. If jumper JP14 is in the A position
only audio from the microphone circuit is recorded. This includes microphone audio and any auxiliary audio
inserted at the UIM rear panel through the plug-in terminal blocks. If JP14 is in the B position all of the
control tones are included in the recording. This option exists for the system operator to be able to debug a
system problem. The system operator will be able to verify which control signal came from the C-6124
console. In this position crosspatch transmit audio will be recorded, as well. If JP14 is in the B position then
JP15 should be moved to the B position to avoid having crosspatch transmit audio summed in twice.
Crosspatch transmit audio may be included with the recording by placing JP15 in the A position. This
jumper is moved to the B position when JP14 is moved to the B position.
6.3.6 SQUELCH CONTROL
Squelch control allows the system operator to set up the receive path so the receive bus will not be driven
unless there is a minimum audio level on the receive path. The squelch control disables this audio gate until
the LAM circuitry activates. The receive gate will allow RX audio through only as long as the audio
maintains a minimum audio level as judged by the LAM circuit. There are three receive audio paths – Select,
Unselect, and Crosspatch RX. Each may be configured with squelch control independently.
Description
Jumper
Position
Select squelch enabled
JP4
A
Select squelch disabled
JP4
B
Unselect squelch enabled
JP3
A
Unselect squelch disabled
JP3
B
Crosspatch squelch enabled
JP2
A
Crosspatch squelch disabled
JP2
B
