Shure A120S - Manual

GENERAL
The A120S Accessory in-Line Switch can be used to
add an On/OFF, Push-To-Talk, Cough Button, or Transmit-
ter-Relay Keying function to a microphone or other device
rated at up to 3 amps ac (0.5 Adc) 125V, non-inductive load.
The switch has gold-plated contacts for reliable perfor-
mance even in low-current circuits. The switch is a double-
pole double-throw type for maximum versatility. Its pushbut-
ton combines with a rotary knob to provide either
spring-return momentary or locking action.
The unit is supplied with a crimp-on strain relief tor
6.4mm (0.25-in.) diameter cable and with a flex relief for ei-
ther large or small diameter cables. The permanently at-
tached belt clip can be rotated on the case to any of four posi-
tions for the most convenience in use.
OPERATION
Switch Function Rotary Knob Position
On/Off (Button remains down
until depressed a second time)
Push-To-Talk (Button remains
down only while depressed) Locking
Momentary
Locking the Switch Button Down
The switch button can be locked down by following
these steps.
1.
Turn the rotary knob to locking.
2. Press the switch button down.
3. Turn the knob to Momentary.
The button will remain locked down until the knob is re-
turned to locking and the button is depressed again.
SWITCH INSTALLATION AND WIRING
1.
For thicker cable (e.g., one 6.4 mm [0.25 in.] diameter
cable or two 3.8 mm [0.15 in.] diameter cables), cut off
the bottom of the flex relief at the rib. For narrower cable
(e.g., one 2.3 mm [0.39 in.] diameter cable), use the en-
tire flex relief as supplied. Thread the cable (s) through
the flex relief.
THICKER OR MULTIPLE
CABLES
SINGLE NARROWER
CABLE
FLEX RELIEF
FIGURE 1
2. For one 6.4 mm diameter cable (0.25 in.), crimp the
strain relief to the cable making sure the eyelet is to-
ward the raw end of the cable. Leave enough raw
cable above the strain relief to permit soldering the
individual conductors to the switch terminals.
NOTE: For all other cables, loosely knot the cable above
the flex relief to form a strain relief. Leave enough raw
cable above the knot to permit soldering the individual
conductors to the switch terminals.
STRAIN RELIEF FOR ONE KNOTTED STRAIN RELIEF
6.4 mm (0.25 in.) CABLE FOR OTHER CABLES
FIGURE 2
A120S In-Line Switch User Guide
27B8064 (BI)
 2002, Shure Incorporated
Printed in U.S.A.