McLelland SW-S1 User manual

Signal Activated
Automatic Switches
Instruction Manual
Model SW-S1 Speaker Level Model SW-L1 Line Level
Automatic speaker and line level switches are suitable for a variety of sound
system
applications from large commercial background music and paging systems, to whole
house audio and home theater systems. Speaker level switching is perfect when two
independent sound systems feed a single pair of speakers. Line level switching is ideal
when two different sources feed a single amplifier or mixer input.
Inputs are indetified as Input A and Input B. Input A is the default input and will pass
through to the output when the switch is in the off state. When a source is detected at
Input B, the switch automatically switches Input Bto the output. When the signal is
removed, the switch will remain the the “B”state, until the delay time has elapsed, at
which point the switch returns to Input A.
Model SW-S1 Speaker Level Swich provides a 12VDC status output, allowing the switch to
triggerexternal devices, or power an indicator. This is an open collector output that is
capable of driving up to a 100mA load. Connection is made via a 3.5mm connector,
positive tip.
Model SW-L1 Line Level Switch provides SPDT relay output, which can be used to
trigger external devices. This relay contact will handle 24VDC, 1A load. Connections are
made via detachable screw terminal strip.
Switches require 12VDC, 200mA (max), AC adaptor is included.
12V DC
150 mA
Status
(Out)
BStatus
B
Status
A
Output
Input A
(Sense)
Input B

Specifications:
Model SW-S1 Model SW-L1
Left/Right Speaker Level Left/Right Line Level
A/B Input, single output
Adjustable off delay from 0.5 seconds to 2 minutes
Adjustable sensitivity
Default to Input A, auto trigger with audio is present on Input B
3.5mm 12VDC, 100mA trigger output (Tip +) SPDT relay output, detachable terminal strip
(18AWG max)
Detachable terminal strip inputs and outputs
(14AWG
max)
L/R Line Level RCA female inputs and outputs
Requires 12VDC, 200mA, AC adaptor included
Rugged metal housing
Dimensions (Incl. mounting tabs and connectors): 1.25” (H) x 6.50” (W) x 2.38” (D)
Installation and Use
Upon initial use, it is recommended that the Sense Level bet set to the mid point, and the Delay be set to the
minimum (fully counterclockwise). Take extreme care when adjusting these two settings, as the internal PC board
controls are very delicate. Adjustment should be made with a 1/8” slotted screwdriver.
The sensitivity should be fine in the mid position for virtually all applications. In cases of false or missed triggering,
it can be slightly adjusted up or down as needed.
When a signal is applied to Input B, you will hear the internal relay click, with corresponding change in the green LED
status indicators. When the signal is removed, the status will almost instantly revert back to Input A. Sometimes it is
not desirable to have the relay switch back to Input A immediately, for example, between tracks on a CD, quiet
passages in a song or movie, or long pauses in a vocal presentation. For these situations, the delay can be set to
bridge the period of silence.
The ideal sensitivity and return delay time will depend upon each individual installation and personal preference.