This post is to show how I modified the power cables (being sold as an option by univershal with these monitors) to give them on off switches and to protect them from short circuits.
The monitors were shipped to me quickly and they arrived in really good condition. I have not yet had a chance to see if the image I am viewing on the monitor is the entire image viewed by the camera (this is important for cropping the book-page with the camera, instead of with software afterwards).
I ordered these monitors wired with the AC adapter because I was curious what that meant and I thought it might be to my advantage to receive it that way. The AC wall adapter that I received with this purchase is an AC power adapter that outputs 12V at 3amps. The end of the AC power adapter that plugs into the two monitors had its ground and positive terminals split so they could provide power to both monitors. Here is an image:
As you can see from the image these are bear metal connectors so if you use these you have to shield them with electrical tape to avoid accidental short circuits (mine shorted out when the plug for the ground wire came in contact with the metal housing of the monitor. Note: these monitors seem fairly fault tolerant and mine works great even after the short circuit). This type of connector shielded with electrical tape makes it difficult to plug and unplug as needed. The monitors came with cables soldered to their power receptacles on the circuit boards. The other end of the cables (the ones soldered to the monitors circuit boards) had the matching connectors for the above pictured cable receptacles coming from the AC power adapter.
Instead of using these I opted to make my own connectors and switches for turning the monitors on and off as needed. First I de-soldered and remove the power cables that were added to the monitors circuit boards. I also cut the bear metal receptacles from the end of the AC power cable. Then put together all the parts I purchased from a local store to re-create the power splitter, on off switches, and connections for the monitor.
Note: The connectors that seem to fit the circuit boards power receptacles were labeled as "size L" at Radio Shack. (I'm not sure if that is a proprietary size label chosen by the store or if it is a standard size).
Here are some additional images and the circuit schematic for the switches: