The 1960s HeathKit Programming systems 

Market launch was in 1977. The ICs on mine are almost all dated 1981.

The one on the right is a barebones computer system, it looks like it has a Motorola 6800 microprocessor, so that one is definitely at least 1974 or later. Basically, it is a very limited computer, it has a processor, some RAM and ROM chips and some basic input-output. Thanks to a basic monitor program in the ROM you can pause the processor, use the keyboard on the right to look at a memory address and then enter some data into the memory address, either data for the processor to use or program for it to run, then make it run that. There is some input-output to the left (Data I/O), so I guess it is connected to the data pins on the processor, so you can send your calculation results to an output like the eight LEDs or something else. RAM is the memory holding whatever current data or programs you are working on, ROM is read-only and has a basic program that lets you see and enter data into the RAM without extra hardware. Key buffer holds onto whatever key values you are typing in before writing them to the processor, address buffer holds onto the memory location where you read write and the data I/O most likely is also some sort of a buffer that has the actual data written to or fetched from the memory location. Control buffers are the logic that makes the processor pause, take a single step or just work normally like your computer does. The breadboard is for sticking some additional chips into it, like some logic gates, buffers, memory, more ROMs, etc. It looks like the one on the left is also some sort of a training kit, my guess it had logic chips coming with it, something like the 7400 series. That said, it is pretty useless without the chips, but you might be able to get new ones, I think. They are still being made, might be just newer process (need less power and do not need the +12/-12 V, for example). You can find some manuals and stuff on Archive-org and Github, just look for "Heathkit ET-3400 Microprocessor Trainer".

Nice! 10/10, would learn a lot of low-level stuff the good old hands-on way.

Looks more like late seventies/early eighties , certainly NOT sixties, all those IC's and microprocessors didn't exist back then, only transistors, diodes, resistors, capacitors, potentiometers and that kinda stuff

You should be really careful about connecting wires to those small holes on the PCB itself, those are likely vias (connecting top and bottom traces of the PCB) and you may end up short circuiting something resulting in damaged components! If you connect an output pin of the CPU to +5V and the CPU then tries to pull it low, the output stage on that pin could be permanently damaged! Also, yes you can certainty get those 74xx series IC-chips even today (I have used a bunch of them to create my own 8-bit CPU like Ben Eater did). Just remember that the 74xx series only run 0-5V and NOT +/- 12 V! - Those voltages are usually only used for operational amplifiers or similar analogue systems.

@jefftranter made a video about the 3200 at ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-eIInXZuFsRQ.html and another about the 3400 at ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-EjYpuwnf2wM.html

What the heck is that?😭🙏 I’m so confused.