User manual

Clear-Com Intercom Systems KB-211/KB-211GM Two-Channel Speaker Stations

Rev. A

1. Set the VOX control fully counterclockwise to disable this feature.

(KB-211GM only)

2. Set the Intercom Level control to a comfortable level.

3. Press the Talk button and speak into the microphone while

turning the Sidetone control slowly back and forth. There should

be a point where the operator’s voice (and any accompanying

acoustic feedback) disappears. This is the null point.

4. Readjust the VOX control. (Refer to “12—VOX Control (KB-

211GM only)” on page 6.)

6—Program Level Control

Adjust the Program Level control to set the program audio level heard in the

headset or panel speaker.

Note:

Forcing the trimpots past their stop points will damage them.

7—Speaker ON/OFF Switch

The Speaker ON/OFF Switch turns the front-panel speaker on or off. This

switch also controls whether the Tone Alert is heard through the speaker. The

speaker volume will automatically dip when the talk function is set, unless the

VOX function is enabled.

8—Mic Select Switch (KB-211GM only)

The Mic Select switch selects whether the panel microphone or the headset

microphone is active. When the VOX feature is enabled, it is only operational

when the panel microphone is active.

9—Channel Switch

This switch selects the intercom channel (A or B) on which the speaker station

is active.

10—Headset Connector

The headset connector is located on the front panel. All Clear-Com headsets

are recommended for use with the KB-211. The Clear-Com PT-4 Push-to-Talk

Microphone or the HS-6 Telephone Handset will also plug into the headset

connector. The following is a description of the characteristics of a suitable

headset:

• Mic Type—Dynamic; 150 to 400 ohms impedance; -55 dB output level

• Headphone—Dynamic; 50 to 2000 ohms impedance.

The wiring of the headset is to be as follows:

• Pin 1—microphone ground (shield)

• Pin 2—microphone hot

• Pin 3—headphone ground