Hello everyone,
I apologize in advance for the lengthy post. I know this thread is old but I have a very relevant question, that I was wondering if you can help me out with. I found an old top loading cassette recorder from the 70's. It's a radio shack / realistic. Well built, got it for voice recording. Anyway, I have some experience with replacing belts and idler wheels on cassette decks, lubing etc... But when I started testing this particular recorder, it had some issues. I will explain these briefly and also have posted a couple of photos of the inside mechanism. I am asking for your help in identifying the issue.
First of all, the recorder is the Realistic CTR-34. Looks very low use. Before opening her up I tested the functions. Here were the results: Rewind = OK. Forward = OK. Play = pinch roller / capstan engages and pulls tape through but left take up spool doesn't turn, tape spills. I opened 'er up, examined the belts, one was a bit loose, so I changed both (with temporary use of rubber bands to verify function). I rechecked function again. Forward and Rewind are very strong but the left take up spool doesn't spin at all (when in play). I then opened the top to view the idler wheels and the rest of the mechanism. (Photos attached).
The pinch roller looks fine, grips well. The capstan spins strong. The heads and tape path look fine. The idler wheels rubber is totally fine, grips well when in rewind and forward. When I press forward or rewind, the idler wheel mechanism either go to the the left or right, which in turn, turns the spools (verified by hand, the spools present with lots of torque). All fine here. When I press play (as seen in photo), the mechanism slides up (which disengages the idler mechanism). I deducted that the idler wheels' only function is to rewind or forward. The play function (take up of tape by left spool) must be controlled by something else. But what?? Are there any belts or additional idlers that are missing there? And where do they go? Can you see anything that I don't see?
From my own visual inspection, the only things which provide any direct movement are the idler wheels (for REW and FF) and capstan (for controlling tape) and the rest are passive. But what controls the left take up spool (when in play)? (Please click on each image for enlarged view).
Thanks in advance for looking and for your help.