Elman 4WBB 4-wire Beltpack Box

by Elman
Elman 4WBB 4-wire Beltpack Box
The 4WBB is a compact battery-powered box for headset use only.
Selectable operating modes suit various applications in a number of studio and outside broadcast situations where 2/4 wires communications are
Direct compatibility with other communications equipment is provided by the use of 4-wires operation as opposed to the more common, 2-wires beltpack systems.
Greater flexibility resulting from 4-wires operation also enables both interrupt and 2-wires modes to be easily selected by user.
The IFB option is typically used to provide an interrupted program feed to a presenter`s earpiece, when the talk switch is pressed, while simultaneously allowing the program sound to be monitored on the headset.
As the signal is switched directly between the input and output connectors, the program signal path is fail-safe and does not require the unit to be powered.
In 2-wires mode, a number of Beltpack units can simply be connected in parallel, enabling all units to communicate with each other in conference mode.
To provide compatibility with earpieces which use a mono jack plug, the tip connection on the headset jack socket supplies the output for the headphones, 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.
4WBB is compatible with similar apparatuses of other brands in commerce.


-Three user selectable modes:
1) 4 wires mode
2) Interrupted loop-trough mode with input monitoring
3) 2-wires conference mode
-9 volt battery powered with low current drain (current 5mA)
-Microphone limiter to maintain peak output at +6dB
-Power for electret microphone (optional - set with internal jumper)
-Auxiliary audio monitoring input on unbalanced 3.5mm jack
-LED low voltage warning: at 6V
-Strong aluminum case


Microphone input / Line output amplifier
-Input impedance: Unbalanced for 200 ohm dynamic microphone
-Microphone connector: 6.35mm headset jack. Ring input, sleeve gnd
-Limiter input threshold: -62dBU
-Line output level: +8dBU peak (battery voltage >6V)
-Output impedance: 150 ohm, transformer coupled
-Line connector: XLR3M

Line input / Headphone amplifier
-Line input impedance: 10K ohm, transformer coupled
-Line input connector: XLR3F
-Gain range: +10dB to off
-Auxiliary input impedance: unbalanced high impedance
-Auxiliary input connector: 3.5mm jack
-Gain: fixed at 0dB
-Max Line/Aux input level: +8 dbU
-Headphone connector: 6.35mm headset jack. Tip output, sleeve gnd

2-Wires mode
- Line impedance: 10k ohm (listen), 600 ohms (talk)

-Dimensions: 120 mm x 78 mm x 43 mm
-Case: Aluminum Alloy, clear Anodized
-Weight: 385g