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Old 4th Mar 2016, 1:21 am   #59
Skywave
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Join Date: Jun 2006
Location: Chard, South Somerset, UK.
Posts: 7,457
Arrow Re: A precision voltage calibrator

Extract from post #51, dated Feb. 29, q.v. . . .

I purchased one of these:

Quote:
Originally Posted by David G4EBT View Post
There are several e-bay offerings at £10 - £15 post free from China of the ‘KKMOON High Precision Voltage Reference Module AD584kH’ with selectable outputs of 2.5, 5, 7.5 and 10V.
Which, upon initial test, also proved to be defective. O/P voltages wrong - very wrong. At present, this matter is unresolved.

--------------------------------

Update, March 4. 2016.

Fortunately, that matter is now resolved, but not without a struggle with the supplier. I eventually received a refund.

So that's now two precision voltage reference units - from different suppliers - that I have here, both faulty. One is simply a pcb with an AD584 plus a few passive components; the other also has several SMT devices on its pcb, in addition to the AD584. Now on the basis that there may a reasonable chance that only one AD584 chip is defective and since I have the datasheet for the AD584, in the established time-honoured tradition, I might be able to make a good one out of the two. After all, what have got to lose? A few hours of my time at worst.

I'll report back later.

Al.
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