Hi Folks: I would like some assistance with the following: Could someone direct me to a simple schematic that will perform this function: Take the low voltage audio call tone from a (family radio service handset) that is heard in the headset and amplify the signal enough to activate a sensitive a small relay of 9-12 vdc coil drawing 25ma ( the type normally found on printed circuit boards). What would a circuit that performs this task be called, so I could do a google search?
Thanks for your help...
Gerry