It is a simple and very old military oscilloscope, possibly made by RCA. It was intended to be used to look at electrical signals in radios and the like, but is still useful today for tracking down noises and intermittent connections in vehicle wiring as well as for general audio and old radio work. Could be used to work on TV sets up to a point. Good for working on traditional Tesla coils, as tube circuits won't be destroyed by high voltage arcs. Usually. No harmful rays are emitted from the device. All the test leads are missing from the lid there. Inside there is about 2000 volts as well as lower voltages like 6.3 to 700 volts. If you find them by accident it it may be a very shocking experience. It has alot of vacuum tubes inside that might be useful. It also has capacitors with PCBs and they may or may not be leaking. It is worth about $25-30 for parts, assuming it is complete. It is not worth much more in working order. If it works and does not catch fire or smoke (a posibility!), you can connect one channel of your am-fm radio's line output to the "Y INPUT" jack and watch the music. If it blows the fuse, don't put a bigger one in it or there may be a fire hazard. Check the fuse to see that it is the amperage rating called for, and no higher. Sometimes the previous owner would have out anything they could find in there. I have seen identifying pics of that item on the internet but cannot find them at this moment. It's really a nice old classic piece of gear. I might have parts if you need them. Enjoy. Or, just ship to me.