Clear-Com KB702GM

The KB-702GM remote speaker station permits the user to select between two channels of party-line communications, with the ability to talk and/or listen on the selected channel. The user can listen via the integral speaker, or may use a headset or telephone-style handset - and can talk via a headset mic, a telephone handset, or a push-to-talk microphone.

The KB-702GM adds a gooseneck-mic connector and VOX circuitry, for hands-free full-duplex communications without a headset. A switch allows the user to choose between the optional GM-9 or GM-18 microphone and the headset connector. The adjustablesensitivity, close-in VOX feature automatically detects the user’s voice at the mic and dips the level of the integral speaker while increasing the gain of the microphone, performing in the opposite manner when listening. The potential for acoustic feedback is minimized while permitting natural conversation levels and dynamics.

Microprocessor-controlled logic and switching yields a feature-rich intercom station in a compact format. Electronic switching for the talk button, blue-color LED (on), amber color LED (off), permits momentary or latching operation. For call signaling, a bright LED lights when a call is activated on a connected intercom channel. A defeatable audible call signal, with level control, is also provided. Separate level controls are provided for intercom level and for balanced program input. A local program source may be fed to the station, allowing the user to monitor that source while remaining in contact on the intercom system. The balanced program input can also be used in conjunction with the stage-announce output of a main station to provide a paging interrupt, allowing paging at the KB station even if the intercom volume control is turned down.

A set of option dip switches is located at the top of the circuit board. Swithces are provided for mic-latch disable (momentary-only talk), long-line operation, channel selection, call signal tracking, and audible call signaling.

These versatile stations may be wall or console mounted in a standard U.S. 4-gang electrical box, or may be mounted in the optional V-Box for desktop, surface-mount or portable applications.

Either of the stations may be used with the optional 4-wire or TW (two channels on a single mic cable) daughter boards. On the TW board, the stations become plug in compatible with a Clear Com TW system. The 4-wire board creates separate send and receive circuits, so that the station may be attached to fiber-optic lines or other audio routing systems with 4-wire connections. The stations are powered by the intercom line or by a local power supply when used with the optional 4-wire daughter board

Features

• Selectable two-channel, full-duplex operation
• Microprocessor-controlled logic and switching
• Momentary/latching talk button
• Visual and audible call signaling, with bright LED indicator
• Balanced local program input with separate level control
• Internal controls for call signal tracking, mic latch disable, and other functions
• Use with headset or handset, with integral speaker for monitoring
• KB-702GM adds mic jack for gooseneck mic plus VOX circuitry
• Optional TW and 4-wire daughter boards provided additional flexibility
• Wall or console mount, or optional V-Box for portable or desktop use
• LED buttons for talk, listen, call, announce, link, all talk, or mic on

Specifications

• Panel Microphone Input
  Input Type: Electret
  Input Impedance: >=2K ohms
  Mic Limiter Threshold: -2dBu ±3dB
  Mic Limiter Range: >= 15dB
• Headset Microphone Input
  Input Type: Dynamic
  Input Impedance: >= 1Kohm
  Mic Limiter Threshold: -2dBu ± 3dB
  Mic Limiter Range: >= 15dB
• Program Line Input
  Maximum Level before Clipping: >= 20dBu
  Input Impedance: >= 5K ohms
• Headset Output
  Load Impedance: >= 8 ohms
  Output Impedance: <= 25 ohms
  Output Limiter Threshold: +5dBu ± 3dB
  Maximum Output Level before Distortion: >= 17dBu
• Speaker Output
  Load Impedance: >= 4 ohms
  Max Output Level before 1% Distortion: 20dBu ± 2dBu
• Party Line Output
  Off Noise: < -74dBu
  Output Impedance: >10K ohms
• Party Line Input
  Crosstalk: < -60dB
  Max level before Clipping : >= 12dBu
  Sidetone Null Capability: > 25dB
• Frequency Response
  Panel Mic - Party Line: 300 - 16KHz ± 3dB
  Headset Mic - Party Line: 300 - 15KHz ± 3dB
  Program Input - Headset Out: 200 - 18KHz ± 3dB
  Program Input - Speaker Out: 200 - 18KHz ± 3dB
  Party Line - Headset Out: 200 - 18KHz ± 3dB
  Party Line - Speaker Out: 200 - 18KHz ± 3dB
• Max Distortion
  Panel Mic - Party Line: <= 0.5%
  Headset Mic - Party Line: <= 0.5%
  Program Input - Headset Out: <= 0.2%
  Program Input - Speaker Out: <= 0.5%
  Party Line - Headset Out: <= 0.2%
  Party Line - Speaker Out: <= 0.5%
• Noise
  Panel Mic - Party Line: < -65dBu
  Headset Mic - Party Line: < -70dBu
  Program Input - Headset Out: < -60dBu
  Program Input - Speaker Out: < -60dBu
  Party Line - Headset Out: < -50dBu
  Party Line - Speaker Out: < -50dBu
• Max Gain
  Panel Mic - Party Line: >= 37dB
  Headset Mic - Party Line: 41dB ± 2dB
  Program Input - Headset Out: >= 18dB
  Program Input - Speaker Out: >= 24dB
  Party Line - Headset Out: >= 34dB
  Party Line - Speaker Out: >= 40dB
• Power
  Input Voltage Range: 20-30 VDC
  Input Current (Idle): <= 90mA
  Input Current (Max): <=110mA
• Internal Adjustments and Connections
  Intercom: Line Five terminal connector
  Program Input Three terminal connector
  Option Switches: Three DIP switches Call Signal Jumper3: Three sets of options jumpers
  Call Alert Tone Level Control: Level adjustment control
• Front Panel Connectors
  Panel Mic: (1) 1/4 in. (0.64 cm) panel mounting jack
  Headset: (1) XLR-4M
• Front Panel Controls & Indicators
  (1) Panel /headset mic switch
  (1) Program monitor level control
  (1) Sidetone null control
  (1) Talk button
  (1) Call button
  (1) Speaker ON-OFF switch
  (1) Channel select switch
  (1) Speaker volume control
  (1) VOX control
  (1) VOX indicator
• Environmental: 32 - 122°F
• Dimensions (W x H x D): 8.25" x 4.5" x 1.75"
• Weight: 1.1 lbs

TMGR# KB702GM