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14x7
11-25-2015, 01:40 PM
anybody on the forum ever ask a electronics expert if there's a way to hook up a tachometer to the 6 volt president , without the electric box from Studebaker ...maybe using advance electronics from the aftermarket....Have a great turkey day...

gordr
11-26-2015, 05:56 PM
This has come up before. There are six volt tachs out there, but they are not easy to find. And most 12-volt tachs are negative ground. I would suggest trying a 12-volt tach, powered by a separate 12-volt battery, say one from a cordless power tool, or even eight D-cells in a box. Use an 0.5 uF capacitor rated at 400 volts between the tach sensor lead and the ignition points. That way the case of the tach can be grounded, and the 12-volt power feed to the tach is isolated from the rest of the car's wiring, even though it shares a common ground with the car's 6-volt positive ground electrical system. Any decent tach should contain circuitry that can recognize and count either positive-going or negative-going pulses, and process them accordingly. If I were trying this, I'd mount the tach, battery, and capacitor on a board, and hook it up to the car with clip leads to test the concept, before going to the trouble of mounting it in the dash. It would be pretty easy to add a relay wired to the ignition switch such that the tack battery got turned on only when the ignition switch is in the "run" position. I expect even a bank of D cells would last for many months in this service.

TWChamp
11-27-2015, 01:53 AM
Model A's are also 6 volt positive ground, and some of the guys use a tach called "Tiny Tach" if I recall correctly.

LeoH
11-27-2015, 01:15 PM
Interesting... http://tinytach.com/index.php

gordr
11-27-2015, 03:29 PM
Lithium battery life, 5 years, not replaceable? And it costs $47.00? And a digital display that would look extremely out of place in an old car. Just not seeing it.

TWChamp
11-27-2015, 07:47 PM
Lithium battery life, 5 years, not replaceable? And it costs $47.00? And a digital display that would look extremely out of place in an old car. Just not seeing it.

I never looked at them, but the non replaceable battery is really a dumb idea, and I wouldn't buy one either.

LeoH
11-27-2015, 09:04 PM
Lithium battery life, 5 years, not replaceable? And it costs $47.00? And a digital display that would look extremely out of place in an old car. Just not seeing it.
I'm glad I'm not the only one who read that explanation that the battery wasn't replaceable. I wonder if that's just written incorrectly. I sent them an email asking if that was the case or not. I'll post their reply.

LeoH
11-30-2015, 09:40 AM
I received this email last week from Tiny Tech:

We estimate the battery life to be 5-7 years, although some have been known to last more like 12-13 years. Part of it depends on how much and how often the tach is used, and how many wraps of the red wire (the fewer wraps, the better). Our website tinytach.com also has tachs with replaceable batteries, depending on what you are looking for.


> It may be how it was worded, but I have the impression that the tiny
> tach lasts only 5 years and then has to be replaced , since the batter
> is not replaceable?
>
> I may be too literal in reading that sentence.
>
> Thank you,
> Leo Horishny
> Sun Valley, NV
>
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