EFJohnson VR-CM50 manual 5.10SET UP AND OPERATION OF THE HEAD- SET JACK, W A R N I N G

CRT-BASED ELECTRONICS ASSEMBLY PART II

1.Remove the hole plug from the left side of the head- set jack housing.

2.Install the volume control (4751904Z5001) in the housing in the place of the hole plug.

3.Connect the three pin molex connector, located on the end of the wire harness, to the volume control. This connector can only be connected one way.

Caution: Be careful not to bend pins when making the connection.

4.Attach the volume control knob (240FPV12BA1).

5.10SET UP AND OPERATION OF THE HEAD- SET JACK

The headset jack is equipped with a switch on both sides of the unit. These switches are slightly recessed to prevent accidental movement. The switch on the right, as shown in Figure 5-7, is used for select- ing 4W/6W operation. Four wire (4W) headsets do not have a push-to-talk (PTT) switch.

W A R N I N G

If a 4 wire headset is plugged into the jack when it is set for 6 wire operation, the channel will instantly key up and remain on until the headset is unplugged.

The switch on the left, as shown in Figure 5-7, is typically used for training purposes. In the MIC On position, the headset MIC and earpiece are active for normal dispatch operation. In the MIC Off position, the headset earpiece is active but the MIC is disabled for use by a trainee in parallel with a trained operator.

Figure 5-7 CONNECTOR HEADSET

5.11CONNECTING A TELEPHONE INSTRU- MENT TO THE TELCO INTERFACE

The telephone instrument must be headset com- patible. The instrument must have a separate mic path and earpiece path. The telephone instrument should also provide a contact closure output when a line is selected. If the telephone does not have this capabil- ity, a key on the Radio Control Panel may be pro- grammed to switch from Radio to Telephone but this is not a preferred method of operation.

Figure 5-8 TELCO CONNECTION TO CIP PS

Note the following abbreviations: TT and TR are abbreviations for Talk Tip and Talk Return. RT and RR are abbreviations for Receiver Tip and Receiver Return. OHS is an abbreviation for Off-Hook Sense. GND is an abbreviation for logic GROUND. Refer to Figure 5-8,Line Term Board A1709230.

1.Connect the Microphone Input to the telephone instrument to terminals TT and TR of the CIP Line Term Board, A1709230.

2.Connect the Receiver Output from the telephone instrument to terminals RT and RR of the CIP Line Term Board, A1709230.

3.Connect the Line Select contact closure output from the telephone instrument to terminals OHS and GND of the CIP Line Term Board, A1709230.

	February 1996
5-5	Part No. 004-3039-274