Ballast testing.

Why bother. Get a new more efficient fixture with T-8 lamps and a good quiet efficient ballast.

I've heard T-8's mentioned a lot recently. Why are they better?

Frankly they are better because they are smaller. Being smaller keeps the heat in the lamp better and they work more efficiently. Most also come with modern electronic ballast and will work well at very cold temperatures without any of the annoying buzz.

Lamps are measured in`1/8's of an inch.. Do not ask me why, I do not know where this came from. T-8's are 1 inch in diameter and are smaller than the standard T-12's. The T-8's also can produce more light for less energy. There are also some high output T-5's available.

Personally I would throw away the ballasts and starters and buy new. Either electronic or magnetic ballasts your choice. Wear gloves when your replacing the old ballasts, they are probably full of PCB's. Do not burn them.

And if you spend much time in the shop I'd recommend springing the extra few bucks for some wide spectrum bulbs; sometimes referred to a "daylight" bulbs. The light from them makes a big difference in your general viewing pleasure and in many cases they seem to brighten up a sagging mood just like going outside on the first sunny day of spring. I've switched to those kinds of bulbs everywhere I can in our home, my home workshop and our office.

Jeff

While you're at it, since it's that old and parts like starters and sockets are sure to begin failing, why not replace all of the electrical components with a

It may be cheaper to just buy a whole new fixture and swap the whole electrical component.

quoting:

What are the bulbs doing? Flickering, completely dead, ends of bulbs lighting up? Anything? IS the whole fixture out, or is it just one or two bulbs?

Is the shop heated? Or actually, can you say "it never gets too cold in there"?

If it's a reasonably warm room, you can get away with a new fixture that uses cheaper tubes (35 or 38W, it's late, can't remember right now) and you could buy a fixture and a case of 10 tubes for less than you would likely pay for replacement parts for an "ancient" fixture and 4 new 40W tubes.

Sometimes, $tuff just ain't worth trying to fix.

half the lampholders, so I did pretty much what you suggested and just went with a new light. BUT.......I'd still like to know if there;s a simple way to bench-test a ballast , or test it in place. Thanks to all for the help.