Thread: mag base remagnetizing
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David Billington[_2_] David Billington[_2_] is offline
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Default mag base remagnetizing
On 17/03/2020 18:06, wrote:
On Sat, 14 Mar 2020 21:25:20 +0000 (UTC), Cydrome Leader
wrote:

Has anybody remagnetized a rotary on-off mag base before? I was thinking
about a large capacitor and some turns of wire on EI transformer core
with the Is removed and the indicator base across the center and one side
leg.

How are these magnetized at the factory?
Probably your best bet is to replace the old alnico magnet with a new
rare earth magnet. This is because if the alnico magnet is removed
from the magnetic circuit it loses a lot of its magnetism. The alnico
magnets in old and/or inexpensive mag bases were/are magnetized after
assembly. This takes a LOT of current. I have seen the setups for
doing this and they are not trivial.
Eric

The magnets in my cheap magnetic bases are black ceramic magnets. I did
once re-magnetise a screwdriver by putting it into a coil of wire and
connecting it a DC power supply as I didn't have any permanent magnets
handy.

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