I suspect this (AC) ammeter also has a removable rectifier in it; the clue is the "dead zone" between 0 and 2A, where the voltage across the shunt is below the band-gap voltage of the rectifier bridge. Looks to be actually 1.4 A, so assuming Si diodes, that tells me the shunt should be close to 1.0 ohms. Isn't it amazing how I can do the "Sherlock Ohms" thing from this far away? Thus my constaint complaint about the negelect of basic physics in today's EE curriculum.
@DrQuine: The new text was on several small spot labels that covered the old text. If you have access to an old lettering guide and a good fine point permanent pen that might also work well for small captions.
I think this option would be very low down my list of solutions -- I want every aspect of my projects to make the observer gasp "Wow -- that is amazing -- let me buy you a beer!" LOL
@Max The Magnificent The new text was on several small spot labels that covered the old text. If you have access to an old lettering guide and a good fine point permanent pen that might also work well for small captions.
Also, nearly all faceplates are symmetric; thus no need to scrape. Just flip it over and paint! I've used that trick many times. If you have an old drafting tool/ pen set, the compass is terrific for draing the scale arc (if you can find some India ink.....). I have a couple of sets (including one older than I am).
PS: examining the photo of the disassembled meter, it has an internal shunt THAT CAN BE REMOVED. That would restore the basic movement range etc. so you can use it! Same for "voltmeters" except the multiplier is often external; if it is internal, it's also easily removable.
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