Sercurity Camera Digital I/O help!!!!!

Thread Starter


Joined Nov 5, 2007
Hello. i am a student right now studying communication engineering, and has been assigned this task of setting up a security camera.

my current task is to design and develope a Digital I/O with isolation...for the RTV-24 which is this thing over here.

I have to use a Opto coupler-Circuit for the Input and a DC relay circuit for the output to the D-connector.

The opto-coupler has to be able to withstand +5V-24V at the least.

The inductive coil is 5VDC, contacts are 24VDC. It is a 5VDC relay.

How should i go about doing this project...such as finding the resistor values, and such pardon me for being such a noob on this...i have not been taught any of it before.


Joined May 16, 2005
Welcome to AAC.

I've just browsed through the manual for the RTV-24. Looks like a halfway decent substitute for a DVR. Halfway.

Some additional information will be needed to understand what you are asking for.

Which D connector do you refer to?

Which inputs need opto-isolation?

Which outputs need a relay?

Note that opto-isolators will eat 24volts for breakfast and complain about the small portions. Most opto-isolators can handle a few thousand volts between isolated circuits.

Thread Starter


Joined Nov 5, 2007
Hello thanks for the warm welcome..i understand my question is rather vague....haha regarding the questions that you have asked...i will need to find them out from my supervisor also haha...