Dead deck coming back to life

[caution]

Hah jimmy We aim to please!
Thanks Bill!
Hey Norm the pads worked great, I just had to cut them down pretty tightly to stay within the confines of the circuit board. I'll hang on to the silver paint for another use. I've seen videos of hammies use these on their handhelds with great success, which is why I picked up a bottle.

Back to the reel motor for a second. As I was rewinding a tape, the motor seemed to be slowing down. It seems like the JVC control chip has some sort of feedback circuit for spindle speed. I could see it possibly reading the Hall sensor's signal (from the right spindle) and noticing that this reel is starting to move faster and faster as the left reel gathers more tape during rewinding, and getting a larger diameter, making the right spindle possibly spin too fast for its own good. Is it possible the control chip is sending a signal with a lower duty cycle to the motor driver chip's inputs, as it notices the Hall sensor pulsing too fast? I'm not sure if you can throttle the reel motor in this way though, and run it at different speeds.

Here's the control panel all repaired

 

[Superduper]

If I were to guess, I would say the slowdown is natural due to the higher load of spinning a larger/heavier reel. Many very unsophisticated Boomboxes will slow down especially towards the end of long c90 tapes.

 

[metalhandbag]

Excellent work and skills a pleasure to read keep it up .

 

[MyOhMy]

If I opened a box to be greeted by the sight of a deck in this condition I would probably sigh, gulp and slowly close the box. Ye gods, you're certainly dedicated with skills in abundance. Excellent work.

 

[Radio raheem]

What outstanding work, i don't think iv seen such indepth photos of the m90 deck like this before, totally amazing, thanks for this thread...