Belt-pack 4-wire box type C1B
The C1B is a compact battery-powered 4-wire box for headset use only. Selectable operating modes suit various applications in a number of studio and outside broadcast situations where 4-wire communications are used.
* Three user-selectable operating modes:-
Interrupted loop-through mode with input monitoring.
2-wire Conference mode.
* 9 volt battery powered with very low current drain (2mA).
* Microphone limiter to maintain peak output at +8dBU.
* Auxiliary audio monitoring input on unbalanced 3.5mm jack.
Direct compatibility with other communications equipment is provided by the use of 4-wire operation as opposed to the more common, line-powered 2-wire belt-pack systems. Greater flexibility resulting from 4-wire operation also enables both interrupt and 2-wire modes to be easily selected by the user.
The IFB option is typically used to provide an interrupted programme feed to a presenter's earpiece when the talk switch is pressed, while simultaneously allowing the programme sound to be monitored on the headset. As the signal is switched directly between the input and output connectors, the programme signal path is fail-safe and does not require the unit to be powered.
In 2-wire mode, a number of C1B units can simply be connected in parallel, enabling all units to
communicate with each other in conference mode. As the unit’s microphone signal is also heard in the headphones, this mode also provides a quick method of testing the correct operation of the unit and headset.
To provide compatibility with earpieces which use a mono jack plug, the tip connection on the headset jack socket supplies the output for the headphone(s), the ring connection providing the microphone input. The auxiliary input jack can be used in all modes to monitor any additional line-level signal such as a tape machine playback, etc..