Will is right. The proper engineering answer is that you need a material
with higher permeability (did I spell that right?). I know that almost
nobody cares but permeability is the change in flux density divided by
change in excitation "force" in a magnetic material. In otherwords, like
will said, soup cans don't have enough iron in them.
Coincidently I've been contemplating the sensitivity of the mag pick up on
these tachs. If you wanted to supply a voltage pulse metallicaly to the
terminals where the "bar" connects across the terminals on the back of the
tach, what voltage need you apply? I'm assuming that the amplifier is
actually a voltage amp but I guess it could be current. I want to use a
spare Series V Alpine tach in an application where a voltage pulse is
provided. I'm thinking I could scale the supplied pulse with some
resistors then apply it to the terminals where the bar attaches.
I could just cut the coil wire and wrap it around the bar and then
re-attach it to the original wiring I guess.
Frank Marrone MK I Tiger B9471116
marrone@wco.com 1966 LTD
'79 Spitfire
Yamaha Seca 900 (aka XJ900RK)
|