Video Switcher

[georgelawshe]

I have two Video Inputs to a single output. I would like a swicher that would constantly switch between the two inputs with adjustable preset "ON" times.
Camera A would be on for 3 minutes then Camera B would be on for 5 Minutes then loop again.

I would like the adjustable times to be from 2 to 8 minutes.

Any ideas? Your help will be appreciated.

Thanks
GeorgeLawshe

 

[twister]

I think a 556 set up as two monostable circuits would work. The outputs could control a relay or transistor to turn on and off your cameras. You would feed back the outputs to the trigger or the opposite timer. I don't know how to draw schematics on the computer but maybe someone else could draw it for you. You would need two variable pots for R1.

 

[georgelawshe]

This is my problem, I can build the circuit with no problem, my problem is designing the circuit, Can anyone help with this?

Thanks
GeorgeLawshe

 

[twister]

Sorry that my first link didn't work.
http://www.kpsec.freeuk.com/555timer.htm
Maybe if you study the 555 circuits you can figure out how to make a circuit work for you. If you go to an electronic supplier you can get a breadboard that will allow you to plug in components to test out your theorys. It is always best to breadboard a new circuit to see if it will work. I buy a lot of stuff from Jameco.com and they seem to have good prices.