Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

12v circuit that stops power output when source power lost

Status
Not open for further replies.

Tyl3z

New Member
I'm looking for a circuit to install in my car from my battery to my subwoofer. When I turn on my car I get feedback for a few seconds. I've created a solution to this by installing a rocker switch inline with the power source cutting power to the subwoofer when I need to. I often forget to turn off the switch when I leave my car and when I return and start the car, the switch is left on and I get the feedback again to my sub.

Is there a circuit I can hook up with possibly a relay and a momentary switch so that when I turn off the car the power is cut to the subwoofer and stays off until I turn it on again with the momentary switch?

Basically I want power to default to off everytime I turn off my car and I have to manually turn the switch on every time I want to use the subwoofer so that I don't forget to turn the switch off every single time I leave my car.
 
Kind of how heated seats work. If you turn off your car with your heated seats left on you don't end up having a warm bum when you turn your car on again later as it defaults to off. I know this is controlled in the computer but can I make a circuit to have the same setup going to my subwoofer?
 
You should connect the remote out wire from your radio to your subwoofers remote + input. This wire is often labeled "antenna remote" (also used for a power antenna). This way your subwoofer will turn on when you turn on your car radio.

If you really want to use a relay instead, Look here at the 2nd circuit:

 
I recommend a soft-start relay circuit from the positive feed with the AF output tied to the relay arm. The NC contact connects to a power resistor to load the amp during power-up, the NO contact feeds the speaker after the timer expires. This should eliminate the feedback you are describing.
 
Status
Not open for further replies.

New Articles From Microcontroller Tips

Back
Top