Hi everyone, I'm new here and pretty new to electronics. I know the basics but thats about it so bear with me.
I recently installed a flashing LED into the dash of my girlfriends car because we cannot afford a proper alarm system. I went out and got some flashing leds and some resistors and put one in. I hooked the positive lead to constant 12v and the negative to the acc so when the car switches on the led switches off and vice versa. While it worked really well the led flashed way too fast to look remotely like an alarm led.
So I dug around on the net and found a scematic for a simple flashing led circuit. I bought the parts and put it all together, tested it on an old pc power supply, it worked. I then went and installed it in the car the same way I did the other one. This time it didn't work, it was feeding the acc 12v when the car was off and the led didn't flash.
Here is a diagram of the circuit i used, only difference being the value of the resistors and capacitor:
Bottom line is, is there anyway I can hook this up so it turns off when the car is switched to acc or on, without powering up the acc line (obviously useless)? I thought maybe a diode or transistor or the like might work but i've no idea on how to wire it up.
Any help would be much appreciated.
I recently installed a flashing LED into the dash of my girlfriends car because we cannot afford a proper alarm system. I went out and got some flashing leds and some resistors and put one in. I hooked the positive lead to constant 12v and the negative to the acc so when the car switches on the led switches off and vice versa. While it worked really well the led flashed way too fast to look remotely like an alarm led.
So I dug around on the net and found a scematic for a simple flashing led circuit. I bought the parts and put it all together, tested it on an old pc power supply, it worked. I then went and installed it in the car the same way I did the other one. This time it didn't work, it was feeding the acc 12v when the car was off and the led didn't flash.
Here is a diagram of the circuit i used, only difference being the value of the resistors and capacitor:
Bottom line is, is there anyway I can hook this up so it turns off when the car is switched to acc or on, without powering up the acc line (obviously useless)? I thought maybe a diode or transistor or the like might work but i've no idea on how to wire it up.
Any help would be much appreciated.
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