4-Channel Remote Headset Station

  • Momentary/Latching Talk switch with LED
  • Microprocessor controlled logic and switching
  • Visual call signaling
  • Headset connector with volume control and sidetone adjust
  • Optional 4-wire or TW daughter boards for flexibility
  • Mountable into a standard US two-gang outlet box
Item Part Number:


The HB-704 is a four-channel-selectable, full-duplex headset station, able to be mounted into a wall or other surface.

Note: Access the Encore Power Supply Calculator to estimate power requirements for analog partyline systems.

Technical Specifications

Headset Microphone Input

Input Type: Dynamic

Input Impedance: >= 1K

Mic Limiter Threshold: -2dBu ± 3dB

Mic Limiter Range: >= 15dB

Program Line Input

Input Impedance: >= 5K

Headset Output

Load Impedance: >= 8

Output Impedance: <= 25

Output Limiter Threshold: +5dBu ± 3dB

Maximum Output Level before Distortion: >= 17dBu

Partyline Output

Off Noise: < -74dBu

Output Impedance: >10K

Partyline Input

Crosstalk: < -60dB

Max level before Clipping: >= 12dBu

Frequency Response

Headset Mic – Partyline: 300 – 15kHz ± 3dB

Partyline – Headset Out: 300 – 15kHz ± 3dB

Max Distortion

Headset Mic – Partyline: <= 0.5%

Partyline – Headset Out: <= 0.2%


Headset Mic – Partyline: < -70dBu

Max Gain

Headset Mic – Partyline: 41dB ± 2dB

Partyline – Headset Out: >= 34dB


Input Voltage Range: 20-30V DC

Input Current (Idle): <= 50mA

Input Current (Max): <=100mA

Internal Adjustments and Connections

Intercom Line: Seven terminal connector

Option Switches: Two DIP switches

Option Board Jumper: Two sets of options jumpers


32 – 122°F (0 – 50°C)


4.5 x 4.6 1.75in (HxWxD)

(114 x 117 x 44mm)


0.46lb (0.21kg)

Associated Products

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