I recall some radars used those large round screens, long persistence phosphors. Often these were mechanically rotated in time with the antenna, with slide contact rings. Later electronic rotation superseded that.
Expansion on your fun fact. Electronic rotation was accomplished with a polar CRT. A polar CRT is a variant of a vector CRT where the beam path starts in the center and extends to the edge in a direction derived from the azimuth of the radar antenna. The transmit pulse would start a new scan from the centre and its speed would be determined by the desired range selection. Finally the beam intensity was just the amplified return signal from the antenna.
All of this required complex electromechanical devices to generate (and eventually filter) the required signals.
As technology progressed and textual information started to be added to the process it became necessary to convert the polar plot to a conventional rasterized signal. This was accomplished with a scan converter tube which was essentially a polar CRT coupled to a TV camera. Radar would plot on the CRT and the camera would turn it into scanlines to be overlaid with data. This was used into the 90s and there's probably still operational systems relying on this.
Being in the air force I have the dubious privilege of getting to maintain some old ass-technology. Radar being amongst my favourites. We've since upgraded to comparatively modern technology (digital!) and gotten rid of most of the vacuum tubes but I still have a special dark place in my heart for the old mixed signal system running on CRTs, wire wrapped boards, tapes, and core memory.
Interestingly while the new system is much nicer to work with, much better resolution and features I didn't think were possible. The old system had power, and lots of it, and sometimes power is what you need.
Tektronix was famous for actual storage screens, where once a signal was drawn across the CRT it would persist until the screen was reset. Very handy for capturing a single event and viewing it at your leisure.
The one I used had a joystick built right into the keyboard, and it ran a CNC programming environment.
Data I/O was paper tape via serial and data cassette. Ours did not have the floppy or fast refresh graphics options.
2048x2048 vector space! The big CRT could resolve most of that when well tuned.
The work process was:
Load editor from tape cartridge
Type it in, or read text from paper tape.
I had punched a fair number of shortcut G-codes and I would use them to get the bones of a new program started.
Write finished program text (g-code) to paper tape. That could and should include comments. (We put a setup sheet on the master tape, for example) This was a master.
Make another stripped down one, and this is production.
Prep a tape for reading by sticking the beginning of program end into the reader and put the reader into handshake mode.
Read it back to validate against program in RAM.
Or...
Load backplotter/ simulator. Prep program tape for reading.
Run the simulator, plotter. If it was a master tape, it would know the tooling setup and just draw all the operations to the CRT. And because it was a storage tube, those all would display and one could see what metal gets cut out easy enough.
This worked fairly well!
Once it was done, the production tape went into a can and was moved to a library. That was a whole wall of cabinets filled with little plastic canisters containing paper tape programs for everything.
1Mhz 6500 CPU.
And like I said, the Tek terminals were just fun to use.
Nice stuff, I was a Tech-Tel officer in the 60's(RCAF) and solid state was slowly penetrating the MIL-space, due to the huge waits for MIL part validation and approval - for want of a nail - a shoe was lost....
I can recall 10K 1/2W resistors in their own package with their own frame of a 16MM filmed x-ray enclosed as repair back stock.
Yes, audit trail was kept and maker and MIL accumulated reliability stats to add more 9's to the tail. Not sure how this persists in the surface mount era as most parts are nine nines reliable now - or more? I have to assume assembly stuff does a lot of real time test with beds of nails. I saw the old blackberry line, when it was scrapped out(after the fall) and every board was nailed and tested, fails = reworked or scrapped. Huge bins of all sub boards etc., in all parts of the process when they were closed = recycled for precious metals etc.
