Sony TC 377 (and others) how does the tape tensioner engage in fast forward?

[pjl52]

There is a tab under the tensioner arm that gets pushed by a spring loaded tab from the sliding assembly.
The spring loaded tab is apparently referred to as "stopper/tension regulator" which is mounted on the "lever (B) interlock".
See the respective dropbox videos to see the lever tab and stopper.

https://www.dropbox.com/s/zf16mi437ba0fky/Video Feb 26, 6 56 33 PM.mov?dl=0

https://www.dropbox.com/s/l9dafopn6pijy3p/Video Feb 26, 6 58 11 PM.mov?dl=0



There seems to be something wrong with how these interact on my machine. (I noted that the tab had been bent a bit back but I straightened it out to maintain 90 deg with the top surface of the tension arm). In "play mode" the (B) interlock lever slides over to the left causing the stopper to push the tensioner tab. That pushes the tensioner arm left to put a b it of pressure on the source reel brake causing some small friction on the source tape. I have adjusted that brake with a felt pad mounded on the top brake arm so tape can unspool under tension. So that works ok.

But when put into fast forward, the lever interlock (B) and stop shifts more to the left pushing the tab and tensioner arm further to the left. That puts great pressure on the source tensioner, locking the source reel in place. Thus fast forward cannot occur.

A small note is that there is no felt in the bottom arm of the "L" brake on the source reel. I cannot seem to put any there and have the reel spool in "play mode".

Is my setup screwed up? I seem to recall a jam in this forward/fast forward mechanism long ago solved by me via brute force.

Also, I do not understand how the spring loaded "stopper" is supposed to work. What is the purpose of the spring?

Thanks to all in advance,

Phil in Rochester NY

 

[pjl52]

Here is a simple question that will help me

ought the tension arm tab lie as shown in the following with respect to the stopper
https://www.dropbox.com/s/sy4bfde122f6vz0/Video Feb 28, 10 55 30.mov?dl=0

or can it be allowed to slip past the stopper as shown here
https://www.dropbox.com/s/xkg11hn47grpj1m/Video Feb 28, 10 58 28.mov?dl=0

if it is the first, then a solution is to put enough braking material in the source brake to prevent tension arm motion as shown in the second video

thanks for looking. Phil

 

[pjl52]

Please ignore this thread. Will post new message about what I learned fixing this Tc 377. The above messages will no help anyone.