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Products => Test Equipment => Topic started by: srruhl3701 on August 13, 2020, 09:13:46 pm

Title: 'uCurrent' circa 1976
Post by: srruhl3701 on August 13, 2020, 09:13:46 pm

While browsing old electronics magazines, I came across a construction project of a miliamp volt meter accessory. It uses a CMOS op amp, and also can measure current with 1 nA full scale on the 1 volt range of the meter.

It is designed for analog meters with 1k Ohms/Volt or greater.

https://archive.org/details/197607PopularElectronics/page/n3/mode/2up

Title: Re: 'uCurrent' circa 1976
Post by: SilverSolder on August 13, 2020, 10:03:55 pm

I guess it would need a zeroing pot, if it is not based on a chopper amp?

Title: Re: 'uCurrent' circa 1976
Post by: joeqsmith on August 14, 2020, 01:30:53 am

Are you referring to the "millivolter" that allows a volt meter to read millivolts?

Title: Re: 'uCurrent' circa 1976
Post by: srruhl3701 on August 14, 2020, 02:01:58 am

Yes, it also has selectable shunts to use for reading amps.