I have 4 scanners and want to route their speaker output into 1 speaker.
I have seen simple circuits to combine the speaker outputs to feed 1 speaker, basically they take the speaker output of each radio, feed it through a 10Kohm resistor, then all the output sides of the resistors connect to a single speaker. Looks simple enough, is that all there really needs to be?
Next I'm looking for a good, low noise audio amp to feed the output of the mixer into before driving the speaker. How much power is typical (watts) and can anyone point me to any good circuits or Audio Amp ICs?
Finally I would like an LED on the input of the mixer to turn on anytime there is audio coming in on that input line. I would prefer an IC that could handle at least 4 inputs that would turn on 4 leds anytime there is audio present. If there isn't such an IC, then a simple circuit?
I have seen simple circuits to combine the speaker outputs to feed 1 speaker, basically they take the speaker output of each radio, feed it through a 10Kohm resistor, then all the output sides of the resistors connect to a single speaker. Looks simple enough, is that all there really needs to be?
Next I'm looking for a good, low noise audio amp to feed the output of the mixer into before driving the speaker. How much power is typical (watts) and can anyone point me to any good circuits or Audio Amp ICs?
Finally I would like an LED on the input of the mixer to turn on anytime there is audio coming in on that input line. I would prefer an IC that could handle at least 4 inputs that would turn on 4 leds anytime there is audio present. If there isn't such an IC, then a simple circuit?