Shure SCM810 manual Suggested Logic Applications, Cough Button, Chairperson-Controlled Muting

SUGGESTED LOGIC APPLICATIONS

This section contains suggestions on the uses of the SCM810's logic capa- bilities. Note that uses of these functions are not limited to the listed appli- cations. The user is limited only by individual imagination and creativity. For additional suggestions and solutions to installation problems, contact Shure's Applications Group.

In the following paragraphs, the wiring diagrams refer to the DB-25 connec- tor pins shown in Figure 4.

Cough Button

The talker can turn off his or her microphone during coughing or private conversations by installing an SPST pushbutton switch between the MUTE IN and Logic Ground pins for each channel to be modified (see Figure 12- Channels 1, 2 and 3 modified). When a channel is muted, no audio is passed. (See “Dead Zone on MUTE IN Defeat” in Internal Modifications section for more information on MUTE IN logic.)

LOGIC

GROUND

M1 M3

M2

COUGH BUTTONS

FIGURE 12

Chairperson-Controlled Muting

The chairperson can, by activating a switch, silence all other microphones and be heard without interruption. For operation in this mode, connect all the MUTE IN pins together except that of the chairperson's channel, and wire an SPST pushbutton or toggle switch between those MUTE IN and Logic Ground pins (see Figure 13-the chairperson is shown as Channel 1).

An alternative to a switch is to connect the chairperson's GATE OUT to the MUTE IN of other channels. When the chairperson's microphone activates, all other microphones mute.

CH. 1

LOGIC

GROUND

M3 M5 M7

Remote Channel-On Indicators

Remote indicators can be used to indicate when a talker's microphone is on. Connect the LEDs and a 5-volt supply to the GATE OUT pins as shown in Figure 14 (Channels 1, 2 and 3 shown modified). To avoid switching clicks in the audio output, do not ground the power supply negative terminal in the audio system or rack ground.

IMPORTANT: If a single cable is used for the microphone audio signal and the LED dc power, separate shielded pairs must be used. Failure to carry the dc power on a shielded pair may result in audible clicking due to capac- itive coupling between the dc power lines and microphone lines.

	+ 5 V POWER –
		SUPPLY
			LOGIC
			GROUND
G1		G3
	G2	R = 470	&!, 1/4 W

REMOTE CHANNEL-ON INDICATORS

FIGURE 14

Disabling the Gating Function (Bypass)

To keep certain microphones on at all times, wire the desired microphone channel's OVERRIDE IN pins together to the Logic Ground pin. The selected channels now function as they would in a non-automatic mixer (see Figure 15-Channels 1, 2 and 3 modified).

LOGIC

GROUND

O2

O1 O3

GATING BYPASS

FIGURE 15

M2 M4

M6

CHAIRPERSON-CONTROLLED MUTING

FIGURE 13

11