I've also noticed some older machines seen in certain television shows myself; for example, I've seen the following at the very least:
- IBM System/370:
I believe that I saw this one once in an episode of Hawaii Five-O, along with the reel-to-reel tape machines.
- IBM Personal Computer (Model 5150) / IBM Personal Computer/XT (Model 5160):
I've seen one episode of Cheers which showed one of these machines running at someone's desk. She was shown typing on her keyboard at that time, and it also had an original IBM display (I think that it might have been a monochrome/MDA display monitor, which would have had the Green phosphor).
- IBM PS/2:
These were very commonly seen in episodes of Columbo from the late-1980s and early-1990s; which is not at all surprising given how many companies very likely had contracts with IBM (and which would also explain why an episode of Hawaii Five-O had an IBM System/370 in it earlier as said above). Infact, for one system, the "Starring the computer" website stated that the machine shown running in the episode "Murder, Smoke and Shadows" was either an IBM PS/2 Model 50 or an IBM PS/2 Model 70.
- COMPAQ Deskpro:
In an episode of Matlock from Season 4, the machine shown running appeared to be a COMPAQ Deskpro; possibly a Compaq Deskpro 386, judging by its case design. However, if it WAS a COMPAQ Deskpro, then it obviously didn't have the original monitor but a generic one.
- HP-86:
This machine was seen in many episodes of Quincy M.E. Season 8, however, for the last episode, they were using Apple II systems instead for some reason.
- Apple II:
As said above, in the very last episode of Quincy M.E., several Apple II machines were shown running.
- Various terminals:
There are probably too many to list here, but in the highly-controversial "kidney donor" episode of Quincy M.E. Season 4 ("A Question of Death"), a computer terminal is shown running in one scene, with either a Blue or Green phosphor display from what I remember.