On Mon, 4 Jun 2012 18:41:30 +0100, "Ian Field"
wrote:

Its a 2-terminal relay for a motorcycle, after adding an earth lead so I
could fit a car type; I then discovered that the intermittent operation was
due to a corroded connector block hidden under the tank.

After breaking up the epoxy potting I found the old relay was blameless.

The circuit could probably be adapted for 6V with a logic level MOSFET - but
would need 2 in parallel to handle twice the current (don't forget filament
cold resistance surge!).


Now *that* is an application for a 555!


--

John Larkin Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
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