Communications Box

[card9inal]

I'm building a communications box for a broadcast situation. Birdman and I are working on this, and we don't see any problems, but could y'all give your two cents and let know if there is something wrong with this design?

I know there are better ways of doing this, and the second iteration will be a great improvement over this one. (This is a bare bones, get me on the air, and a backup system in case I don't get the big one done in time!)

The program feed would be interrupted and dimmed with the microphone when the button is pressed...

Thanks everyone!

 

[kchriste]

I guess that will work. Hard to tell without knowing the rest of the circuit. You might want to make the resistors adjustable. Why are there so many outputs? Why are they all fed from one PGM input and one MIC input?

 

[card9inal]

What else about the circuit would you need/like to know? The reason there are so many outputs is each one will be a headphone feed for an announcer. The program feed will be what they hear in their ears as they broadcast. The Mic input is the microphone of the producer, who will need to talk to them individually.

The resistors won't necessarily be adjustable (I've contemplated having them though) but I'm going to test a bunch of them out to find the right volume of dimming to achieve the best result. It's one less thing to worry about accessing when it's all assembled!

Let me know what else you need to know!

Thanks

 

[kchriste]

Unless you intend to make a proper mixer board with line level input and outputs, you need to know the audio levels and the source impedance and load impedance of all the equipment attached. Otherwise, there is no proper way to choose resistor values and sound levels will be hit and miss. I would buy/build a proper mixer board with OpAmps if it was me.

 

[card9inal]

It will be a line level input for both the program input and the mic input. How would you wire this to be a better solution?

It's not going to be so much a mixer (though in a very odd way, it is) as it is an IFB. The point is for it to be interrupted with the mic audio. Not mixed particularly well. The quality doesn't need to be great, as its all "behind the scenes" type stuff.

What would make it work properly?

Thanks!!!