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Rookie help with power on trigger mod

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vincent9993

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I recently purchased a vehicle webcam that I plan to mount permanantly in the car. To start the cam and start recording I need to press the Power button then press the Rec button.

I would like to know if and how I caould mod the circuit to have those circuits triggered upon receiving external power.

Anyone care to direct me in the proper location?

Thanks.
V
 
Two parts to the problem. First, you need to open the device and figure out if the buttons are mechanically latching, or if they are just a momentary contact, normally open type of switch. Check how many poles there are on the switches. Use a voltmeter to measure the voltage at both sides of the switch contact(s), measure relative to the ground wire that ties to the car.

Second, you need a circuit to generate the appropriate delays, and to simulate the switching action of what the switches do. You can't do this till you understand what is happening in One, above.
 
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Thanks for the quick reply, the switches are not mechanical and looks like there are 4 pins on each switches. I think I only need to momentarily close the circuit in sequence to trigger the on/off and start recording. Are there any similar project I could read up on to get this accomplished?

Thanks.
V
 
You could trigger the power button instantly and use a 555 timer in monostable mode or a comparator and a capacitor to generate the delay to the REC button.
 
You could trigger the power button instantly and use a 555 timer in monostable mode or a comparator and a capacitor to generate the delay to the REC button.
Generating the delays is the easy part. The big question is where are pushbuttons in the circuit. Are they on the high side?, low side?, is one end grounded or not? What is the open circuit voltage being switched? How much current? Are the switches multiplexed, scanned, etc?
 
Yes, I know, but we would require more information on the circuit for that. Maybe even a picture would do.
 
I'll get you fine support people a picture of the circuit, in the meantime, here's a link to the actual camera in question:
**broken link removed**
 
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