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In the spirit of Locost
dave1888 - 11/3/06 at 01:24 PM

I found this on the net. Can't cost that much to make.
http://martybugs.net/electronics/speedo.cgi


chrisg - 12/3/06 at 11:13 AM

looks good but I was out of my depth in the second paragraph.

I'm not good with electrickery

Cheers

Chris

[Edited on 12/3/06 by chrisg]


MikeRJ - 12/3/06 at 09:58 PM

It won't cost much, but it would be much simpler and very likely cheaper to use a micro such as a PIC instead of the discrete logic. It will also be far more stable, that design has it's clock derived from a 555 timer IC which will not be particularly stable over time or with temperature changes.


chrisg - 13/3/06 at 09:33 PM

Yes, that's what I thought.

You definately need a wibble capacitor to enbongalate the resitivator.....

Cheers

Chris


MikeR - 13/3/06 at 10:29 PM

i thought that if i removed the 555 timer and the wibble capacitor both could be replaced by some uranium housed in a flux capacitor. This would give a much more stable time signal - although would be subject to some other minor environmental issues.


Peteff - 14/3/06 at 12:20 AM

Weapons grade plutonium would be better I think with a strontium core condenser, flux capacitors are so 90's.


MikeR - 15/3/06 at 12:09 AM

yeah but i like retro - thats why i'm building a replica 50's sportscar!


Patching Cars - 19/3/06 at 10:28 PM

quote:
Originally posted by MikeR
i thought that if i removed the 555 timer and the wibble capacitor both could be replaced by some uranium housed in a flux capacitor. This would give a much more stable time signal - although would be subject to some other minor environmental issues.


But wouldn't that limit you to a top speed of 88 mile per hour without unwanted side effects?

I quite like the idea, and have added it my collection of useless circuit designs along with my digital boost gauge.