I designed digitasl meters with automatic 1 ohm steps. I took the wheatstone bridge apart and made 4 terminal connections to the unknown.
One lead was the supply return, it;s rresistance unimportsnt, connected to it at the unknown was the digital pot in one ohm steps to 9.99 ohms. the other end went to the range resistor, 10 times the unknown full scale. The chopperr detector connected there. I put a resistor 10 ttimes the digital pot and to the bridge supply. I haed 4 leadgold plated clips to connectt to the uknown. It measured to 9he low scale. It autoranged to 9.999 megohms.
E samuel Levy. I have never seen tthis connection.
One lead was the supply return, it;s rresistance unimportsnt, connected to it at the unknown was the digital pot in one ohm steps to 9.99 ohms. the other end went to the range resistor, 10 times the unknown full scale. The chopperr detector connected there. I put a resistor 10 ttimes the digital pot and to the bridge supply. I haed 4 leadgold plated clips to connectt to the uknown. It measured to 9he low scale. It autoranged to 9.999 megohms.
E samuel Levy. I have never seen tthis connection.
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