Shure SCM810 - Manual (Page 10)

10
ADVANCED FUNCTIONS
LOGIC CONNECTION SPECIFICATIONS
The logic functions of the SCM810 expand the mixer's range of installation
and control options. Logic can be used for everything from simple cough
switches to elaborate computer-controlled room systems. (Shure's AMS
Update publication contains additional applications of advanced logic. This
publication is available by contacting Shure's Applications Group.) The fol-
lowing logic functions are available for each channel:
GATE OUT: Follows channel gating and goes to logic “low” (sinks current)
when microphone is gated on. 500 mA of current sinking ability is provided
(see Figure 10A).
LOGIC EQUIVALENT CIRCUIT DIAGRAMS
FIGURE 10
MUTE IN: Applying logic “low” (from GATE OUT or a switch closure to logic
ground) gates channel off (see Figure 10B). Channel output drops to -∞.
OVERRIDE IN: Applying logic “low” (from GATE OUT or a switch closure
to logic ground) forces channel on (see Figure 10B). Factory setting pro-
vides that when both Mute and Override are activated, Mute takes prece-
dence (see Internal Modifications for Override precedence).
LOGIC GROUND: Logic ground is distinct from the SCM810 audio ground.
Make all logic ground connections to this pin, including power supply
ground of external logic circuitry. To avoid switching clicks, do not connect
logic ground to audio, chassis or rack grounds.
Logic controls are accessed at the DB-25 multi-pin connector on the rear
panel (Figure 11). The pin connections are given in the following table.
LOGIC CONNECTOR
FIGURE 11
LOGIC CONNECTIONS
The SCM810's Advanced Functions are recommended only for those who are technically knowledgeable and familiar with audio
electronics.
GATE
OUT
LOGIC
GROUND
FROM
SCM810
TO
SCM810
MUTE IN
OR
OVERRIDE
IN
55K 10K
+5 V +5 V
A B
CIRCUIT
CIRCUIT
Logic Function Input
Channel
Connector Pin No.
GATE OUT1
GATE OUT 2
GATE OUT 3
GATE OUT 4
GATE OUT 5
GATE OUT 6
GATE OUT 7
GATE OUT 8
1
2
3
4
5
6
7
8
1
15
4
18
7
21
10
24
OVERRIDE IN 1
OVERRIDE IN 2
OVERRIDE IN 3
OVERRIDE IN 4
OVERRIDE IN 5
OVERRIDE IN 6
OVERRIDE IN 7
OVERRIDE IN 8
1
2
3
4
5
6
7
8
14
3
17
6
20
9
23
12
MUTE IN 1
MUTE IN 2
MUTE IN 3
MUTE IN 4
MUTE IN 5
MUTE IN 6
MUTE IN 7
MUTE IN 8
1
2
3
4
5
6
7
8
2
16
5
19
8
22
11
25
Logic Ground all 13
LOGIC GATE 1
MUTE 1
O’RIDE 2
GATE 3
MUTE 3
O’RIDE 4
GATE 5
MUTE 5
O’RIDE 6
GATE 7
MUTE 7
O’RIDE 8
O’RIDE 1
GATE 2
MUTE 2
O’RIDE 3
GATE 4
MUTE 4
O’RIDE 5
GATE 6
MUTE 6
O’RIDE 7
GATE 8
MUTE 8
GROUND