Specifications

Section 4 — Equipment Description
4.1 Functional Description
The AFS-1 is designed to monitor one or two audio signals and provide a relay contact
closure as long as at least one of the audio signals is present. When neither audio signal
is present for an adjustable delay period (7 seconds to 4.5 minutes), the relay contact
opens and remains open until one or both of the audio signals return. The AFS-1 was
designed to provide a means to turn a device off (or on) remotely by discontinuance of an
audio signal.
A typical application of the AFS-1 is to provide an alternate control means for a remotely
controlled broadcast transmitter. When appropriately installed, the AFS-1 can be used to
turn off a transmitter by discontinuing the audio feed to the transmitter. This procedure
would normally be used only when the normal remote control means had failed.
4.2 Physical Description
The AFS-1 is contained in a small "modem-sized" case (5.5" x 5.5" x 1.75") and can be
mounted in any convenient location such as on a wall, inside an equipment rack, or it
may be rack mounted with an optional kit. A 12 volt AC "wall plug" transformer (supplied)
is connected to the AFS-1 and provides power. Audio and relay connections are made on
"pluggable" screw-terminal connectors on the front panel. LED's are also included to
show when audio is present and when the relay contact is closed. A switch is provided to
force closure of the relay contacts and defeat operation of the AFS-1.
The audio sensitivity and relay timing of the AFS-1 are factory set to values which will be
satisfactory for most applications. These values can easily be changed, however.
Instructions on how to accomplish this are located in the "Modifying Operating
Parameters" paragraph in Section 5 of this manual.
Version 2.00 Equipment Description page 4.1