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Old 4th Jun 2018, 11:26 pm   #10
The Philpott
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Join Date: Aug 2016
Location: Colchester, Essex, UK.
Posts: 4,081
Default Re: Meter Suggestions for Basic Alignment/Calibration

Voltage references are quite cheap, i got one which supposedly came from china (the parcel label indicates it came VIA vietnam) It came with an accuracy certificate (to 3 decimal places) based on tests using an Agilent (The certificate indicated the Agilent hadn't been calibrated for 18 months, but then again what do you calibrate an Agilent with!?)

Anyhew, it only cost about £5, and gives 2.5v 5v 7.5v and 10vDC and can supply enough current to avoid the reference warming up too much even on an early AVO. (Particularly if the test is brief)

The only downsides- it came without 100% adequate packaging and only survived due to luck....& it is a naked circuit board which needs setting into a project box. Voltage references from that part of the world tend to quote 23 or 25C as their best ambient, not too far off the 20C that i'm accustomed to seeing.

Immensely satisfying to get an 8/9 avo as good as it was out of the factory. With the wartime military models you sometimes end up with it better than it left the factory.
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