Clear-Com MS-702 - Manual (Page 16)

C l e a r - C o m ®
M S - 7 0 2 T w o - C h a n n e l M a i n S t a t i o n I n s t r u c t i o n M a n u a l
2 - 1 0
Pin 1 --- Ground (shield)
Pin 2 --- - Signal
Pin 3 --- + Signal
The audio output is balanced and transformer isolated. It has a 600 ohm
impedance and a nominal output level of 0 dBV. A shielded twisted pair
cable should be used in the cable wired to this connector.
24. Relay Out: A dry set of relay contacts is provided through a 1/4-in. (0.64
cm) jack to activate external switching as needed when the announce
button is pressed. These contacts can be used to control an external device
such as a PA amplifier to another room. The contacts are rated for 2.0 A at
24 VDC. The contacts are wired as follows:
Ring --- Normally closed contact
Tip --- Common contact
Sleeve --- Normally open contact
25. Hot Mic Out / IFB System: This connection is a 1/4-in. (0.64 cm) phone
jack. It provides a 0 dBV output signal from the selected headset or panel
microphone. This output is intended interface with the external line-in
jack on Clear-Com’s IFB System.
The jack is wired as follows:
Ring --- Ext. IFB control signal input
Tip --- Hot mic audio output
Sleeve --- Ground (shield)
27. Headset Audio Limiter: To protect the hearing of the user, the headset
audio limiter restricts the maximum audio level heard in the headset. The
MS-702 unit is shipped with the headset audio limiter on. You can turn
this feature on or off by using a jumper located on the main circuit board.
To turn the audio limiter on or off:
1. Please observe anti-static procedures. Circuit cards can be damaged
by static electricity. Please ground yourself and tools before touching
any circuit cards.
2. Disconnect the unit from AC mains electricity.
3. Remove the cover of the RM-702.
4. Locate the three-pin jumper labeled “J3” on the center frontmost
portion of the circuit card.
5. A jumper plug is located over pins 2 and 3. This is the on setting.
6. Do one the following to turn the audio headset limiter feature on or
off:
•
To turn the feature on, place the jumper plug over pins 2 and 3.
• To turn the feature off, place the jumper plug over pins 1 and 2.
7. Replace the cover of the RM-702.