# Making a phantom powered power switch (not mute switch) with LED indicator

I want to create an XLR inline power switch (with indicator) so that I can turn my phantom powered microphone on and off as I please!

I have found a few guides online that explain how to create a mute switch, but I'm not sure that will work for what I require.

I've read that an XLR cable has 3 pins, and that you run all of the pins to themselves, 1 - 1, 2 - 2 and 3 - 3 and then you mute the microphone by making a connection between pin 2 and 3, and this shorts the microphone and disables the audio. So this means that when the switch is on, the microphone would be muted.

I want to add one of these these inline to the XLR cable and how I want it to work is that when the switch is on, the microphone and LED on the switch are both on, then when you switch it off, they both turn off.

How would I go about wiring the switch so that when it's in the on position, pin 2 and 3 are disconnected, and then when I switch it off, pins 2 and 3 connect and it shorts the microphone and turns it off?

I'm an absolute novice at electronics, I've learned everything above from researching so absolutely any help would be appreciated!

simulate this circuit – Schematic created using CircuitLab

Figure 1. (a) What you want. (b) What you're considering using.

You need a switch with two normally open (NO) contacts and one normally closed (NC).

The switch you've chosen has only one contact and two terminals so I suspect that the LED common connection is through the body of the switch and requires mounting in a panel connected to negative. (That's usually easy on a car dashboard.)

It is not suitable for your application.

simulate this circuit

Figure 2. The requirements can be met with a double-pole, double-throw, 2P2T, switch.

• Fantastic, thank you for explaining that, I think it makes sense! So if I take the LED out of the equation, what is the simplest switch type I could just to just say 'when in on position, don't short pin 2 and 3, when in off position, short 2 and 3'?
– S_R
Commented Apr 29, 2020 at 22:27
• I've given you that information in the answer. Commented Apr 29, 2020 at 22:29
• Ok, thanks again for your help, its appreciated!
– S_R
Commented Apr 29, 2020 at 22:30