put the adapter in the refrigerator for an hour or two

find the seam that closes the outer halves.

lay the thing on a concrete surface, (it must be absolutely non-movable)

gingerly whack exactly on the seam, go rouund it a few times

most ultrasonically welded units will fracture at the seam, some chemically
bonded will refuse to open, they require a jewelers hacksaw to splitt the
case.

whenu get inside, dip the xformer in a good brand of varnish, then bake the
thing for a couple hours at 250F in an oven

most buzzing is caused by poorly wound (looselywound) wires around the core
that migrate as the unit experiences warm/cool cycles. some thinly applied
manufacturing varnishes fail easily and then the insulating varnish on the
actual coper wire wears and then you get a nice short that often will
entertain u with a bang or flash or complete destructive fire of your
home/business ;-))

all good reason to buy good adapters whenever u can


wrote in message
oups.com...
I have no experience with electronics except dabbling with a
multimeter.

I wanted to silence a humming transformer, I read somewhere that
covering it in JB Weld would do the job. But I didn't even get that
far.

I struggled to open it up, in the end I managed it quite 'easily' with
a hammer.

Before even putting on any JB Weld, I put the lid back on it and
plugged it in.

Then I flicked the mains power switch and bang it blew.

I know it was the ACDC adaptor because and not a mains plug fuse
because the power cord still worked in another ACDC adaptor

Is there a way for me to open one of these things without encountering
that?
does anybody know about silencing humming / whining transformers