Buzzing Fluorescent

[Ivan]

I have a two-tube fluorescent desk lamp that buzzes too annoyingly to use, but it's a terrific lamp otherwise. Any ideas how to silence it?

[terry]

There is likely a thing called a ballast (a sort of transformer) inside lamp base, (not much info provided to go on!) and it may be slightly loose.Tighten the screws holding the ballast. Glue the ballast in place/place or jam a piece of something softer maybe cardboard between ballast and the box/frame etc. Twist the metal case of the lamp base holding the ballast so it doesn't vibrate. Add weight to bottom of lamp base? Pour in some cement or heavy glue ............. ! In other words do everything possible to stop vibration due to the 60 cycle (In North America) frequency of the electrcity being supplied when the lamp is switched on. Maybe the clamp of the ballast itself is slightly loose? We once had a fluorescent tube lamp in the upper part of a cooking stove that also buzzed, we rarely used the lamp anyway; seemed to be more of a dress-up item than much practical use. Later found that one end of the small ballast, which looked much like a small transformer was secured by one sheet metal screw, while the other end was just tagged slightly loose into a metal slot. Cheap factory labour saving construction? Twisting the tag stopped the vibration; took all of five minutes. Kept the ballast somewhere when we later scrapped the stove.

[jeff_wisnia]

If it does have a magnetic ballast, and tightening the ballast mounting doesn't work you could try what an office maintenance worker "tought me" a long time ago.

Dismount the ballast, hold it in one hand and give it a couple of whaps on its side with the ball end of as BP hammer. Make some minor dents to tighten the case against the ballast lamination stack.

Jeff

I't worked for me a couple of times already.

[Don Klipstein]

Sounds good to me!

But anyone else doing this needs to know to hammer over the lamination stack as opposed to the winding!

The lamination stack is the rectangular portion sticking out in the two longest dimensions. The winding is what bulges up and down from the middle of the lamination stack.

(The winding is around a "center leg" of the lamination stack, and goes through two holes in the lamination stack. The lamination stack is the "iron core", made of a kind of steel optimized for this purpose in large part by mixing in silicon to reduce its electrical conductivity. The lamination stack is made of E-shaped and I-shaped thin sheets/laminations of this "silicon steel". The winding is around the "center leg" of the "E", and the "I" is placed against the tips of the 3 legs of the "E".

In most lamp ballasts using an "E-I core" as well as some specialty transformers where the primary winding conducts significant DC, and many inductors made with E-I cores, the E pieces point the same way so that a nonmagnetic gap (often paper) is added in the "magnetic flux circuit" between a stack of E pieces and a stack of I pieces. In some lamp ballasts, the E-stack is even welded to the I-stack at the edges, which causes a minor increase in eddy current loss. Otherwise, especially with transformers handling pure AC, the E pieces and I pieces are interleaved.)

So, I offer some details of ballast and transformer construction so that others trying to silence a ballast with a ball-peen hammer know where to pound! Pound against the lamination stack - not the winding!

- Don Klipstein ( [e-mail])

[sligoNoSPAMjoe]

...

...

Or replace it with a modern electronic ballast.

[Don Klipstein]

How about a photo?

That ballast has a metal case consisting of a few pieces, including two rectangular sheets each having a bulge to accomodate the winding. One of those two bulged-out plates is visible in the photo.

Another photo:

[Twayne]

If you have xformer experience, then it should be easy to visualize that the buzz is simply comiing from the "plates", usually but not always E shaped, because two or more adjacent ones have become able to move about and that movement creates the "buzz" as they hit each other. There really isn't any lasting solution and hitting with a hammer is likely to cause other problems; if it's too annoying, the only real solution is to replace the ballast.

HTH,

Twayne`

[clare]

that!!!

[Don Klipstein]

I believe that I even have likely one of these, possibly 2-3, somewhat- buried in my home or minimally-buried in the back room of my "day job" workplace (as in when I am *actually on that site* as opposed to being outside for delivery duty).

I would agree that the technology for those is at least 30, fair chance

40-plus years old as of 2010. I am guessing that such beasts might have been made heavily in the 1950's and 1960's.

- Don Klipstein ( [e-mail])

[Don Klipstein]

If you are to try a "hammer whack" attempt, do it in either of the longer 2 of the 3 overall dimensions. If you resort to hammering in the shortest of the 3 main orthoganal dimensions, then you have need to err only on the side of caution in that direction before hammering with more force anywhere (preferably in either or both of the two longer of the 3 main orthogonal dimension ditrections).

Back to "X-ray glasses" - I find those to usually work better on women than on men. And I get "more in the mood" by undressing a gentleman than a lady down to skin-tight underwear whether in actuality or with my eyes and mind. Not that I want to ban, restrict or regulate or add an extra tax onto "cheap X-ray glasses" because they have a tendency to show some clothed human bodies (as in of the gender having higher rate of wearing closer-fitting and/or pocketless clothes in USA) in a way that is more pleasing to my fellow gentlemen that have sexual orientation of the majority one as opposed to mine...

- Don Klipstein ( [e-mail])

[The Daring Dufas]

I once tried to undress a woman with my eyes, then my lashes got caught in her zipper.

TDD