Mauri says;
>Once I saw a tricky method where a limited DC current was set to flow
>into a receiver relay contacts to overcome the oxidization problem.
Exactly what I've done on my FT102 to cure the renowned relay problem.
The technique was well known in the days of Strowger telephone
exchanges.
>Actually, magnetical histeresis causes the core to temporary become a
>magnet.
The telephone relays used in the old British Post Office Strowger
exchanges had either a 'residual stud' of copper on the end of the armature, or
even a brass screw to adjust to prevent realys sticking through residual
magnetism.
Reversing the coil is not an infallible cure, but works often enough to
make it worthwhile trying.
73
Peter G3RZP
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