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From: José Otavio O. de Almeida (no email)
Date: Sun Jun 20 2004 - 14:55:13 EDT
You can recover the compass by applying a strong manetic field on it. You
can do that by winding a coil around the compass, and applying DC
(continuous current) on it. The coil plane should be perpendicular to the
plane of rotation of the compass. The compass "needle" should be left free
to rotate, so that when you apply dc to the coil, it will align itself to
the magnetic field generated.
Try, say about 50 turns of AWG 24 or 28 wire, and apply 12v DC from a car
battery. The contact should be brief, less then a second, as the current
will be very high, almost a short circuit. If you leave it connected it will
generate a lot of heat and burn.Just scratch the contact a few times, that
shoud do it. José Almeida.
-----Mensagem original-----
De: Navigation Mailing List
[mailto:]Em nome de Zvi Doron
Enviada em: domingo, 20 de junho de 2004 04:47
Para:
Assunto: Recharging Compas Magnet
Hello,
I have a small emergency field compass that was kept unused in a pocket on
my mountain bike for the last 10 years. I took it out recently and
discovered it had become very sluggish. I suspect that the magnet under the
compass card has lost much of its power and canot overcome the friction
between the compass card and the needle it floats on. I cannot open it to
get to the needle and clean its tip.
Is there a way to recharge the magnet? I tried placing the compass overnight
on magnetized objects like my phone handset or a large screwdriver but I
suspect I need a stronger source of magnetic field. A 220V wire leading to
an operating house appliance perhaps?
Any advice would be much appreciated.
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