> One thought was that a transistor biased by the system voltage
> could be used
> to simulate the resistance of the fuel guage sender, this would also need
> to have an external voltage reference of some sort to keep the
> voltage level from affecting the guage reading.
Er, but I thought that was the point, to have the voltage level affect the
gauge reading ?
<VBG>
Dave has gently pointed out that I was thinking only of the TR3 fuel gauge
... the early TR4 fuel gauge is a voltmeter (of sorts) and might make an
easier conversion. Since it actually responds to power (which is the square
of voltage), the result will probably be pretty non-linear, but that's
exactly the way the later voltmeters were, so at least it will be authentic.
> I could bias the transistor to use the
> full swing of the guage. I'll bet there's many ways to do this.
Sure there are. You could even hook up a Basic Stamp and have it measure
the voltage, then look up a calibration curve and drive the meter.
> The Ammeter may show zero or full
> swing (depending on if your car is on fire or not)
The neat thing about the ammeter (IMO) is that it shows full swing _before_
the car catches fire. The later voltmeters respond so slow that you can
smell the smoke, be pulled over and out of the car before they manage to
drop to zero. The ammeter gives me time to try turning everything off
first.
Mine also goes full charge whenever I start the engine with a low battery,
letting me know that even though the battery voltage hasn't come up yet, the
battery is being charged. I guess you could say the key difference is that
the ammeter tells you what is happening right now, not what happened a few
minutes ago.
> I guess, at the end of the day, we all like these cars - that in
> some way like doing things the hard way or we'd all be driving newer cars
> with computers and valves you don't have to adjust.
Well put !
> After finish sanding all
> the spokes on all my wheels, this seems like a cakewalk.
Yow ! I'm just barely enough of a masochist to clean and wax them once in a
blue moon. I'd much rather drive the car than work on it.
Ciao
Randall
PS, I checked ... it's gauge, not guage. Even for the British.
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