Rdl Radio Design Labs St-Acr1 Stick-On Line-Level Audio Controlled Relay

the STA cr1 is a precision cost-effective audio controlled relay that provides an active open collector and switches to amp double pole double throw relay contacts when it detects line level audio when audio is absent for a period of one half to five seconds the open collector and relay contacts are switched off the sta cr1 detector input may be connected to a line level output of balanced professional equipment or unbalanced consumer products each of these sources provides a different level into the sta CR one requiring the modules input sensitivity to be adjustable adjustment is simple with the audio source active adjust a multi turn trimmer until the signal is detected as indicated by the LED when the audio signal is no longer present the sta cr1 weights a specific amount of time to be certain the audio is remaining off and then shuts it's relay and slave output off the delay is adju