Re: Bad Idea: Put 9V Flasher LED on top of 9V Battery??

From: John Miller (me_at_privacy.net)
Date: 06/19/04 

Date: Sat, 19 Jun 2004 15:40:05 GMT

NoMailPlease wrote:
> I also ran across a flashing circuit that's supposed to last a year at
> http://www.discovercircuits.com/L/lite-flash.htm. If I keep going through
> batteries or don't get brave enough to attach to the car battery, I might
> just build it and see how it performs.

Standard disclaimer: use at your own risk, etc.:
Because you mentioned that you were relatively inexperienced in electronics,
the expression, "attach it to the car battery" is a little scary. It
sounds like you might be thinking of attaching directly to the battery,
which requires both fusing and the knowledge of how to design and install
it safely (without risk of burning the car or yourself).

The right place to tie in is at the car's fuse block. That's the
distribution point for electrical power.

You'll want to find a circuit with a small-value fuse (e.g., 5 amp) that is
energized with the key off, and find a wire on the fused side of that
circuit (when the fuse is pulled, it's dead). Then you can just tap into
that wire using one of those 3M insulation displacement connectors (no
stripping, cutting or soldering). Voila! And you're protected against
accidental short circuits. 

-- 
John Miller
Email address: domain, n4vu.com; username, jsm
In good speaking, should not the mind of the speaker know the truth of the
matter about which he is to speak?
                -Plato

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