On 18/03/13 04:58, Frank wrote:
On Mar 17, 10:56 am, raypsi wrote:
On Saturday, March 2, 2013 11:00:49 PM UTC-5, Frank wrote:
Clamshell-looking enclosure on small AC power transformers. Magnetic

shielding to prevent interference with nearby wires?

IMO it's an electrical code requirement or navy military designation every military grade transformer I've see is hermetically sealed

True of the several WWII / Korea vintage transformers in my junk
box.

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A metal enclosure (apart for mechanical protection) can be avoided by
using toroid transformers ,similar to RF toroids ,not requiring a
shielding can like cylinder shape inductors with or without a ferrous
core ,which need a screening can.

Frank GM0CSZ / KN6WH