Hello...
I have an old photo studio speedlight (Speedotron) that is
starting to buzz and overheat. Actually, it's the AC mains
XFMR, but as the unit warms...and the transformer starts
to bubble......yikes!, amazingly the strobe unit still works.
I'm obviously in need of a new transformer.
I know that old transformers tend to delaminate, but what other
maladies do they suffer?
Can they just overheat from failing insulation, or other aging issues?
I realize rising current draw could cause similar behavior, but I'm
assuming age as the factor in the transformer for now. Is this a foolish
assumption? (25 years old)

Les KA9GLW

"les" wrote in message ...
Hello...
I have an old photo studio speedlight (Speedotron) that is
starting to buzz and overheat. Actually, it's the AC mains
XFMR, but as the unit warms...and the transformer starts
to bubble......yikes!, amazingly the strobe unit still works.
I'm obviously in need of a new transformer.
I know that old transformers tend to delaminate, but what other
maladies do they suffer?
Can they just overheat from failing insulation, or other aging issues?
I realize rising current draw could cause similar behavior, but I'm
assuming age as the factor in the transformer for now. Is this a foolish
assumption? (25 years old)

Les KA9GLW



old transformers never die... they just faraday..

just kidding

look up vacuum impregnation of transformers for one.

age+use (a well made transformer on the shelf might last a few hundred
years)
thermal cycling is probably the biggest factor. overloads and repeated
excessive surges (aka lightning) will take their toll.
sometimes environmental factors weigh in... excess humidity, corrosive
atmosphere, Murphy, even vibration. im sure my list here is not complete.

time to put Mr Bubble in the dumpster and dial up Speedotron for a
replacement before you have a fire or inhale poison gasses or something.

"les" wrote in message ...
Hello...
I have an old photo studio speedlight (Speedotron) that is
starting to buzz and overheat. Actually, it's the AC mains
XFMR, but as the unit warms...and the transformer starts
to bubble......yikes!, amazingly the strobe unit still works.
I'm obviously in need of a new transformer.
I know that old transformers tend to delaminate, but what other
maladies do they suffer?
Can they just overheat from failing insulation, or other aging issues?
I realize rising current draw could cause similar behavior, but I'm
assuming age as the factor in the transformer for now. Is this a foolish
assumption? (25 years old)

Les KA9GLW



Usually they only fail if overheated, sometimes they do delaminate and get
noisy but that's harmless other than being annoying.

On Tue, 18 Oct 2005 23:11:07 -0500, "les" wrote:

Hello...
I have an old photo studio speedlight (Speedotron) that is
starting to buzz and overheat. Actually, it's the AC mains
XFMR, but as the unit warms...and the transformer starts
to bubble......yikes!, amazingly the strobe unit still works.
I'm obviously in need of a new transformer.
I know that old transformers tend to delaminate, but what other
maladies do they suffer?
Can they just overheat from failing insulation, or other aging issues?
I realize rising current draw could cause similar behavior, but I'm
assuming age as the factor in the transformer for now. Is this a foolish
assumption? (25 years old)

Les KA9GLW

Assuming it is not being overloaded bubbling yet operational,
implies some shorted turns in one of the (usually) hgher voltage
windings as they have the higher resistance coils. So, it;s
overloaded but still supplies enough voltage to be useable.

Even assuming no abuse through overheating, insulation can dry up
and cause problems especially with many tapped coils,

In article ,
les wrote:
I have an old photo studio speedlight (Speedotron) that is
starting to buzz and overheat. Actually, it's the AC mains
XFMR, but as the unit warms...and the transformer starts
to bubble......yikes!, amazingly the strobe unit still works.
I'm obviously in need of a new transformer.
I know that old transformers tend to delaminate, but what other
maladies do they suffer?
Can they just overheat from failing insulation, or other aging issues?
I realize rising current draw could cause similar behavior, but I'm
assuming age as the factor in the transformer for now. Is this a foolish
assumption? (25 years old)

One thing to look at is if the bridge rectifier has RFI suppression
capacitors across it. Had a smoking mains transformer caused by one going
short circuit (disc ceramic)

--
*Speak softly and carry a cellular phone *

Dave Plowman London SW
To e-mail, change noise into sound.

"les" writes:

Hello...
I have an old photo studio speedlight (Speedotron) that is
starting to buzz and overheat. Actually, it's the AC mains
XFMR, but as the unit warms...and the transformer starts
to bubble......yikes!, amazingly the strobe unit still works.
I'm obviously in need of a new transformer.
I know that old transformers tend to delaminate, but what other
maladies do they suffer?
Can they just overheat from failing insulation, or other aging issues?
I realize rising current draw could cause similar behavior, but I'm
assuming age as the factor in the transformer for now. Is this a foolish
assumption? (25 years old)

I'd guess there is a shorted turn.

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