Computers & Mobile Craft & Design Technology
Circuitry, Anatomy, and Repair Tips for Common CFL Lamps

I don’t know about you, but I’m so used to the paradigm established by old-style incandescent bulbs that when one of my CFL’s “blows out,” it doesn’t even occur to me that I might be able to repair it in the garage. Or at least, it didn’t until I saw this page from Pavel Ruzicka, which does a good job of explaining the general principles of operation of CFL lamps and gives great details about their most common failure modes. Apparently, replacing a single capacitor will often do the trick. [via Hack a Day]

12 thoughts on “Circuitry, Anatomy, and Repair Tips for Common CFL Lamps

  1. In my experience I’ve more often found that the bulb was burnt out but the internal driver board is still good. Many parts have been scavenged for use in other projects from workplace CFLs that no longer light. Credit goes to Arnie Coro of Radio Habana Cuba’s DXers Unlimited show for giving me the idea.

  2. Most cfl bulbs at my place seem to go because of fluctuating circuits. The bathroom is on the same circuit as the toaster oven on the other side of the wall. Making the bulb dimable would be nice.

  3. I’d say that about 80% of the electronic failures today are caused by capacitors. Not counting physical damage but that is very easy to diagnose.
    My checklist these days is. a. has it correct power? b. is there physical damage? c. is capacitor bulging or out of tolerance?

  4. Looking forward to testing this out. Too many of the CFL’s around here die because the circuitry has toasted. The tubes still light if you connect them up to a good electronic ballast.

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I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I am a long-time contributor to MAKE magazine and My work has also appeared in ReadyMade, c't – Magazin für Computertechnik, and The Wall Street Journal.

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