What is good way to convert PC display (VGA) output to video-s so that it can be recorded on CCTV equipment?

I have a set-up where one workstation drives 8 monitors via two 4-head video cards. I'm looking for a way to record everything that happens on the monitors.|||the easiest way is with a patch cable or converter both are readily available rather cheaply on e-bay search for : vga to video-s