This is the Sony PVM-411, a set of early 1980s black and white CRT monitors in a 19″ rack mount enclosure. Each monitor is 4″ diagonal and takes composite in via BNC connectors with a passthrough to connect multiple monitors together with the same video signal. Since these monitors are so small, nearly any kind of video you put in will look great on them. I tested video on the monitors with a 2000s Sony Handycam, my Panasonic NV-H75 VHS player, and a video terminal that I had assembled a while ago. I played Recorded TV, Movies and TV Show tapes and all looked fantastic on this small monitor set. These CRTs must have not got a very large amount of usage as there is no burn in and the picture tube is still very bright.
I need to get into these monitors to clean the potentiometers as adjusting the contrast causes the picture to go fuzzy until the potentiometer has stopped being moved. These monitors are very easy to get into, only requiring the removal of 4 screws per monitor. Once this has been done the monitors pull up and out, causing the front knob covers to fall off after forgetting to remove them.
Sony has designed this funny connector that gives each monitor power so that you don’t have to remove any cables when removing the monitors from the rack.
Once out you can see right into the monitor enclosure as there is no bottom panel. There is 4 screws to remove the top/side cover of the unit, two on each side. Once removed the cover pulls up and off. Now we get a full look into the complex internals of this tiny monitor.
Moving to the front of the monitor where the knobs are located, there is two screws to remove, releasing the front panel consisting of the adjustment knobs and the power switch. The front panel can then be removed by pulling back and rotating the panel to get it out. WD-40 was then sprayed into the potentiometers to clean them up. I then cleaned the inside of the monitor, getting dust off the CRT and circuit boards.
Once put back together the contrast knob now works perfectly.