INSTALLATION
To install the ALK-2, attach either a 1/8” stereo plug or pair of RCA plugs to each of the two
switched ports, and also to the common port. Attach the supplied 12VDC coaxial power plug to the
2.5 x 5.5mm power jack, and apply 12VDC at 100 mA. The center pin of the DC power jack is
positive.
OPERATION
Desktop / Local Operation
When connected as shown above, pushing the pushbutton on the front of the ALK-2 selects
between the two connected ports. The LED corresponding to the selected port will illuminate,
indicating which port is the active port. An audible click will be heard each time the pushbutton is
toggled. This is the sound of the internal relay clicking.
Note that if no DC power is applied to the ALK-2, the selection defaults to Port 1, and no
LEDs will illuminate. You can take advantage of this situation to create your own “remote mode” as
shown below:
Remote Operation
For mobile installations, or installations where it is not convenient to place the ALK-2 near the
operating position, it is possible to employ a “remote” mode. This “mode” uses the fact that the
ALK-2 relays are non-latching relays, and will revert to their normally closed position when no
power is applied.
To use “remote” mode, push the pushbutton so that it is in the “in” position. Port 2 will be
selected. To remotely switch the ALK-2, you must place a switch (not supplied) in line with the DC
power to the ALK-2. When power is applied, the relays will click on, and Port 2 will be selected and
the Port 2 LED will light up. When power is removed from the ALK-2, Port 1 will be selected, but
no LEDs will be illuminated.
In this manner, if remote operation is desired, you simply have to mount an on/off switch near
the operating position, and use that switch to toggle power to the ALK-2. So long as the pushbutton
is pushed in on the ALK-2, this will allow remote control of the port selection!
APPLICATION INFORMATION
The ALK-2 may be used to switch up to two circuits plus ground between two ports for any of
a number of types of signals. Be sure to keep the signals within the absolute maximum ratings of the
ALK-2. Signals must be less than 32V at 1 amp.
Examples
•
Stereo audio
•
Mono audio plus composite video
•
CW paddle / key
•
Headphone audio
•
Computer speaker audio
•
Linear amplifier control voltages
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