Meter Shunt Repaired

Each shunt wire is of a specific gauge capable of carrying a specific amount of current. Each wire also has an ohms-per-metre parameter so that for larger resistances you do not end up winding large amounts of wire.

Bulgaria is Open for Business

The exact resistance wire was extremely difficult to find. I contacted many firms in the UK, unfortunately, many were not interested in helping, and others were more interested in making money from postage by charging excessively. In the end, I managed to get an approximate wire from a seller on eBay in Bulgaria. Although the wire was slightly thinner, it was enamelled and had a slim chance of working.

The Doc Saves the Day

Just as I was about to install it, I received a visit from "The Doc" who wanted to park his DeLorean outside.

"Don’t use that wire!" he said

He then continued, “I’ve got some original stuff at home! I remember paying a visit to Avocet House back in 1959 and got several reels of the stuff! I also picked up some new Avometers whilst I was there! “

"Hey, thanks Doc." I said.

The Doc is the only one I know who keeps old stock. He has the complete series of Avometers still in their original packaging. All of his test equipment is made by the AVO Company, including signal generators, and valve testers. He started collecting because during the cold war era he was certain that nuclear war would occur and he did not want to be stuck in his private bunker without any toys to play with...

As you can see, for the high current ranges, they are using a thicker gauge wire for shunt construction. Usually these remain intact and never burn.

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