Today I decide to replace the belts on my Chelco 1010 program recorder. Some time before and waiting the belts to arrive (thank you Ken!) I have prepare that with the change of all capacitors, pinch roller and heads cleaning, and replacing the red led with another green one.
Have you ever noticed any of you if the stock red led illuminate normally or very poor? In my condition this led was light very poor, and after investigate the problem, I see cause the resistor who supply it with power was wrong. To work a generic led at 12 volt dc (on Chelco unit is 9 volt ac but after the bridge diode is 9 x 1.41 = 12.7 volt dc) usually needs about 1 Kohm resistor.
My unit for some reason had 8.2 Kohm. What about yours?
Also a tip to other member with the same device. Even if your unit work like a charm, you must replace at least the 7 little electrolytic capacitors. These are five x 4.7uf, one x 47uf, and one x 1uf. In my condition they where all dry. Plain paper!![:-D]()
Have you ever noticed any of you if the stock red led illuminate normally or very poor? In my condition this led was light very poor, and after investigate the problem, I see cause the resistor who supply it with power was wrong. To work a generic led at 12 volt dc (on Chelco unit is 9 volt ac but after the bridge diode is 9 x 1.41 = 12.7 volt dc) usually needs about 1 Kohm resistor.
My unit for some reason had 8.2 Kohm. What about yours?
Also a tip to other member with the same device. Even if your unit work like a charm, you must replace at least the 7 little electrolytic capacitors. These are five x 4.7uf, one x 47uf, and one x 1uf. In my condition they where all dry. Plain paper!
