K7ITM wrote:
I'd suggest you either find a calibrator to connect your meter to, or
make something you can use as a transfer standard. Maxim, for example,
has some reasonably low cost voltage references with good stability
(very few ppm/C).

Yes, that's pretty much what I'm looking for. The only problem with
Maxim is that they have SO MUCH good stuff it makes it hard for me to
find what I'm looking for. I'll try a more directed search.

Then calibrate the transfer standard against some
known in-calibration volt meter or calibrator, at a known temperature,
and use it.

Yes, I can do that. I already have a temperature controlled environment
for my frequency sources.

I'd think in Scottsdale you could find a calibration
service that would do the job for you, or maybe you know someone who
has access to an accurate voltmeter. Of course, you should really do
it for several ranges. You can maybe calibrate a voltage divider
yourself, but it would save a lot of trouble if you could just do it
directly. If you don't know anyone who works with more accurate
instruements regularly and don't want to pay for a calibration, perhaps
you could pay a visit to the EE or physics department in Tempe and use
one of their instruments.


All good points. I have friends at ASU that could help with this, but at
the end of the day it still has to come home with me. Back to the
transfer standard issue.

I've thought of making a secondary standard myself--I have several of
the reference boards from HP3455 DMMs that have single specific things
wrong with them, but combining them I have at least one good voltage
reference, and one good DC 10:1 divider.


Hmm. The unit in question is a HP3478A. It has a 'CAL' button, but I
haven't hunted for a manual yet so I dont know what it does. Any ideas?

Don't EVER expect to get to voltage measurements with accuracy or even
repeatability like you can with frequency

Oh no, I wasn't expecting that. Even my comment about 1e-5 was really
tongue-in-cheek. However, I really can't point to anything in my shack
that can even approach 1e-2 in any repeatable way as far as voltage or
current measurement goes. I just feel that in this day and age I should
be able to do better that that.

73 Alf NU8I