This is of course the permanent magnet you have all come across.
After the war, they used this technology to create a version of the 601 with a permanent magnet.
This was because strong permanent magnets were not readily available at the time.
Permanent or hard magnets create their own magnetic field all the time.
As the train passes, the permanent magnet sets the system.
These materials form what we refer to as "permanent magnets".
Permanent magnets also require special care when they are being brought to their site of installation.
It was used to make permanent magnets for use in small electric motors.
A "permanent magnet" is a piece of a special substance which makes a magnetic field around it.
Another proposed design uses an array of permanent magnets to create the field.