Wikipedia notes: The system will "draw" images by filling in areas of the screen with color one line at a time; it is not known whether this is an effect employed for the student's enjoyment or if it is due to the slow processing time of the system.
That said, I find it grating when I watch programs like Microsoft Teams draw themselves visibly, like old Windows 1.0 programs.
[0] The graphics logic is entirely custom, implemented in a Toshiba gate array, and it isn't something well-known like a TMS9918A or something else based on that design.
Similar to how Pixar made their first movie about toys because CG made everything look plasticky back then and they realized they couldn’t get away with making a movie with humans or animals on screen for the whole movie.
The best creative people lean into the limitations of technology.
You would choose either channel 3 or 4 from the external RF adapter, or a switch on the game console itself.
There were not any recognized markets where different TV stations were broadcasting on both 3 & 4 within the same realistic radio range.
Remember, when Atari moved beyond mere game consoles to the more decently powerful home computers, it was a drop-in wiring replacement for the previous unit at home. They booted fast to ROM game cartridges, and plenty of people turned them off when they were done playing, but others tried to keep them powered at all times to maintain high scores in games that didn't support saving them.
One cartridge was not a game, it was for programming Basic, and booted to the immediate command line. This one didn't retain any code you would write so probably more people kept their Atari or Commodore on 24/7 then if possible, if they were doing some programming.
IOW your programming environment was always just one of many channels on your TV remote, it popped up instantly, and was right where you left it previously.
Unless of course an "Evil Maid" came along with bad intent, but it was usually an errant vacuum cleaner or rambunctious pet that did the deed :\
I come across Vtechs semi-regularly in places like thrift stores & flea markets. And wouldn't mind having a go at some.
The model discussed here seems fairly hacking/modding friendly (discrete Z80, cartridge port etc). But I suspect most Vtechs are dirt-cheap, undocumented ASICs + tiny LCD screens. No fun hacking that (besides ~0 collectors value).
My dad also had got a Tatung Einstein which never worked. Last time I went back to India (I moved to the US for higher ed) I opened it up and was excited to see that they are a bunch of chips that they taught me in Comp 101 (they were basic TTL flip flops). I brought it back with me.
I still have it, and one day I hope to have enough time and space to open it up and translate it into an FPGA as a way to brush up on my basic digital signal knowledge.