Yep. Everything going into this switcher will need to be genlocked. It has no internal processing to handle non-sync sources. I would guess that your cameras have a Genlock input so they will work. The DVD player and the computer will most likely require a frame sync between them and the switcher to work. All of the sources will require a genlock reference signal. a sync generator with multiple black burst outputs would be the best. A sync generator with a single black burst output going into a Video DA would work as well. Even a black burst generator with multiple outputs can work, but make sure that it is designed to work as a true generator. Horita makes a fairly inexpensive one that will work for you. Every source, including your switcher will need this reference signal to lock to. Each source will need to be “timed” into the switcher for both Sync phase and burst phase. The Grass 110 has a number of maintenance modes that make this fairly easy to do. Hopefully you have the manual. It explains how to do it. If not, you should be able to find a copy on line somewhere. It was a popular switcher in it’s day. Although cheaper than a newer digital switcher with built in frame syncs on the inputs, it will require a fair amount of tweaking to get it set up correctly. If you are good with older analog systems, you shouldn’t have too much of a problem. If this is all new to you it might be a good idea to seek out someone to help you set it up and explain how everything works together for the first time. The overall resolution on your computer input will be pretty fuzzy since this is a composite switcher and just doesn’t have the bandwidth to pass the highly detailed computer signal. You will also need some sort of the scan converter on the output of the computer to change the video into the composite format. It’s a solid switcher, but it’s not “plug and play”. It’s going to take some work to get everything to work together.
E=MC2+/-2db