cup core

cup core

[′kəp ‚kȯr]
(electromagnetism)
A core that encloses a coil to provide magnetic shielding; usually has a powdered iron center post through the coil.
References in periodicals archive ?
Wales' superstar cup core rose to prominence in the land of the rising sun as Shanklin, Stephen Jones, Dwayne Peel, Gareth Thomas, Kevin Morgan, Shane Williams and Michael Owen all proved their international qualities on tour to Japan in 2001.