I had a couple of those machines which I bought from the local school board. On the left side, by the tape counter, is a pause lever, which holds the tape stationary with the drive running. The idea is to pull the lever forward to the lock position, engage play or record, let the capstan run up to speed (that machine has 3 speeds, 7 1/2, 3 3/4, and 1 7/8 IPS), and, when ready, release the pause lever. Also, to the left of the erase head is a little wire lever, which appears to be stuck on your machine. That is the auto stop, which shuts off the power when the tape runs out. Held back in the on position by the tape, it is supposed to fall forward, turning the power off, when forward or reverse are engaged and no tape is present. Two versions of the TC-105 exist: the TC-105, with a two prong plug and pressure pads for both heads, intended for home use, and TC-105A, with a three prong plug and pressure pad on the erase head only, intended for commercial/institutional use..
In the '80s, I was eyeing my Uncle- and Aunt's reel-to-reel recorder. When they were moving to Las Vegas, they gave it to me. The pinch roller was the only thing wrong with it.
I have a Sony home tape deck similar to this. It just gets no power and i can't figure out how to take it apart. It's been sitting on a shelf for 5 years. Eventually, I should get around to working on it.
Got the same tape recorder 20 years ago at a thrift store. let it sit for last few years. Just took it out and spent hours cleaning all the goop and that lever was a fight. Had to twist a Flathead to pry it off with oil on the shaft while twisting it. Cleaned with rubbing alcohol lubed with gun oil. Now its free. Still have issues with capstan roller might get a stronger spring or rejuvenate the wheel somehow. Also that lever won't fully retract so its annoying trying to switch the tape. Everything is smooth but the lever is either bent or needs a bigger roller off cam?
Great video. I noticed that the linkage which took two days to release has a prominent crack in it - if it's anything like the old Akai cams which were made of pot metal it could shatter. I would be tempted to put a nylon cable tie around it just in case if that's possible