How to repair electronic choke for 4' tube light?

Tried to repair to electronic chokes of 4' tube light but cdn't succeed. I'll be grateful if any one can provide a step by step guide with test voltages etc. at important points in the ckt.  Already done/checked - Physical checking of any damage/burn marks etc., DC voltafe after rectification is OK, Filter capacitor after rectification is chkd OK, other electrolytic capacitors chkd. OK, one of the 13005 transistors was found defective - changed but no result, Voltages at the transistor terminals chkd and seem to be OK. May pls contact


rickharris9 months ago


Jack A Lopez9 months ago

Whu...wait. One little apostrophe mark means, "feet". Two little apostrophe marks means inches. I think.

Did you ever see that movie, Spinal Tap? There was a part in that movie that involved some confusion over some measurements that were maybe in inches, or maybe in feet.

You probably mean one with a length of four feet, like for a ceiling fixture, instead of one of the little four inch length ones, like for a flashlight.

I think those tubes often have funny names like, F40T12, or F36T8

A circuit diagram would be nice, and maybe Google(r) Images can help find one or two. Here is a search for, "t8 electronic ballast circuit"

There are a few diagrams there that look possibly meaningful. The only way to know for sure is to follow the links, like this one,

which happens to have two 13005 transistors in it.

Is it the same circuit you are describing? I do not know.

So you want a, uh, "step by step guide"?

Perhaps such a guide is out there, and I wish you good luck in finding it!

Perhaps you could write this guide, in the event you discover what is wrong with your ballast, and you discover what is the way to make it work again.

Downunder35m9 months ago

You need to learn more about patience as two topics for the same stuff is something I would consider spam....