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Anybody know how to test an instrument voltage regulator? I have voltage to the regulator - i.e. I have battery voltage at the wire that comes from the ignition switch and connects to the "ign" terminal at the IVR.
Thanks gents.
 

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Actual average voltage is 5.5v to 5.7v with an analog meter. If yours is bad and you build your own replacement with a 50-cent 7805 voltage regulator, add a diode to the ground leg to push it up to 5.7 regulated volts. Your gauges will be most accurate at that voltage, though they can be adjusted to whatever you have.

David

This pic is of an 8-volt version, but the 7805 (5-volt) version is identical. You can even stuff them inside the old IVR case as many sellers on FeeBay do. Unfortunately, they don't bump the voltage with the diode and it outputs a bit too low for Fords:

 

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Discussion Starter #5
Well, I did put the test light on it and it blinked - like a flasher. I took this as a good sign. A while back I installed a new sender and the gauge still didn't work and I grounded the wire and still nothing. So after checking other things - the flashing IVR, etc., I checked continuity of the wire back to the sender and it turned out to be a bad connector at the sender. I redid the connector to a little spade type and now the gauge works. (I'm probably still going to carry an empty gas can in the trunk though.)
37Mark - that's a great article.
gasman - that's exactly what it did. I at first thought I had a bad connection with my test light. I was expecting dimness instead of a pulse.
PSIG - that's also a great article.
Thanks gents.
 

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Actual average voltage is 5.5v to 5.7v with an analog meter. If yours is bad and you build your own replacement with a 50-cent 7805 voltage regulator, add a diode to the ground leg to push it up to 5.7 regulated volts. Your gauges will be most accurate at that voltage, though they can be adjusted to whatever you have.
Hi David, (I know, I'm a post grave digger....) I just installed the LM7805 in my 65 and stumbled across your post mentioning the addition of a diode to the ground leg. I have two questions for you, 1. How do i select the diode correctly ( I have a bunch laying around, but am not savvy to sizing one correctly, ie how much current it needs to handle out this ground leg...). 2. As I'm currently just grounding the chip to the CVR case by bolting it down, (middle leg is unconnected inside my CVR case) do I need to isolate the case ground to add a diode to the middle leg, or are they not actually the same ground path somehow? ? (Forgive me if that was a confusing way to word it...)


Thanks for your help!
 
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I replaced mine with a USB voltage regulator, which is 5 volts. I also use that circuit to power a cell phone charger port.
 
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I replaced mine with this. Nice case and very inexpensive, $6.

DROK Waterproof High Efficiency Car Power Converter DC12V to 6V/3A Step Down Voltage Module 9-22V to 6V Power Supply
 

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