RDL ST-ACR Series Audio Controlled Relays are used in any application where an audio signal must be used to create either a relay closure or Open-Collector output to control another piece of equipment or a circuit. Common applications include:
- Juke Box overrides Background Music AN-2024
- Silence or “Dead Air” Sensor in broadcast environments
- Automatic adjustment of audio levels AN-2042
- Adjusting audio levels to compensate for high ambient noise AN-2030
- Controlling visual indicators
- Recalling a Preset in a DSP
The ST-ACR1 and ST-ACR2 are both actuated by line-level audio. The threshold sensitivity can be adjusted to trigger on signals between -30 dBu and 0 dBu. When the audio signal drops below the set threshold, an adjustable delay timer is triggered prior to de-actuating the relay contacts. The adjustable delay duration is the major difference between the two relays:
- ST-ACR1 Adjustable delay ½ second to 5 seconds
- ST-ACR2 Adjustable delay 5 seconds to 50 second
The ST-ACR1M is actuated by microphone level signals. The threshold sensitivity can be adjusted to trigger on signals between -65 dBu and -20 dBu. The delay is adjustable between 500 milliseconds and 5 seconds.
Each of these devices are equipped with DPDT contacts rated at 220 Vdc,125 Vac, 2A and an Open-Collector (Slave) output for controlling other RDL or third party products.
Like all of the other RDL STICK-ON™ products, ST-ACR Audio Controlled Relays are designed and manufactured in the U.S.A.