[time-nuts] AC reference voltage

[Neon John]

Generating the AC isn't a problem.  For 60 hz, a variac is fine.  For higher
frequencies, an audio transformer, for example, a plate transformer, and a signal
generator will do the job.  You don't need any power since a DVM has a high input
impedance.  You only need the voltage with enough drive to handle the circuit
capacitance.  A plate transformer run backwards will do the job.

You still must have a standard to compare to.  It should be between 3x and 10x the
accuracy of the instrument you're testing.  One of my favorites for this role is the
Fluke 8800 5.5 digit DVM.  This is an oldie but a goodie.  It was one of the premiere
meters in its era and so there were a lot of 'em in use.  That means that there are a
lot of 'em surplus now.  I have several in my lab and I've never paid more than $50
for one, usually a lot less.  My experience over several decades is that the 8800
holds its calibration as well as any non-microprocessor instrument I've ever worked
with.

John


On Tue, 25 Dec 2007 14:01:02 -0800 (PST), Randy Leifer
<redrabbitlosangeles at yahoo.com> wrote:
>I don't need super accuracy, just within reason to
>ease my mind. I have some decent gear already:
>http://i5.photobucket.com/albums/y177/Midiot/DSCN2695.jpg
>...and a few units, what I believe  to be close to
>"secondary references".
>Frequency intrigues me, but my main hobby is to test
>my DIY hi'end audio gear. So, I have: audio distortion
> meters, AC voltmeters, low distortion audio freq
>generators....that I'd like to check if they are close
>to their factory specs. And I have most of their
>manuals/cal instructions too.
>
>(btw, when I said "power amplifier" in my original
>post, I am refering to an audio power amplifier.)
>
>=Randy=
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
What do you call 4 Blondes in an Abrams?  Air Tank.