[Test-Equipment] Simple DC Voltage Standard?

[GandalfG8 at aol.com]

In a message dated 01/03/2011 01:24:04 GMT Standard Time, n4buq at knology.net 
 writes:

What I  was wondering is how close should a fresh AA battery be to exactly 
1.5V?   From what I can find online, all the specs state a AA battery's 
"nominal"  voltage is 1.5V but I'm not sure how close to exactly 1.5V is 
considered  "nominal".

Oddly, the HP410C measures a fresh AA batttery at exactly  1.5V while the 
other two see it as about 1.625V.  I'm pretty sure 1.625V  is quite high for 
a "nominal" AA and perhaps the Fluke and Triplett are both  out of 
calibration about the same amount.

Any suggestions on a "dirty"  way to get really close to 1.0V?  I also have 
a Tek 465B 'scope but that,  too, isn't calibrated so not sure how that mi
ght help get me where I want to  be with this.




----------
Don't even think about batteries as calibration sources, there's just  too 
many variables, age temperature etc etc, to make it worth the  effort.
 
Similarly, trying to assess which of three uncalibrated instruments might  
be closest to calibration based on mix and match comparisons is also asking 
for  trouble, the two that agree could just be equally wrong but even if 
they're not  how will you know?, and scopes were never intended to be 
replacements for  calibrated meters.
 
Faced with a similar problem I went for one of these......
 
_http://shop.voltagestandard.com/Voltage-Reference-Model-VREF-01-VREF-01.htm
_ 
(http://shop.voltagestandard.com/Voltage-Reference-Model-VREF-01-VREF-01.htm) 
 
They're very good value, Doug is very helpful, and it's little to pay  
considering the confidence factor that comes with it.
 
I have no vested interest, usual disclaimer stuff, but just a very  happy 
customer, you really can't go wrong at the price.
 
Regards
 
Nigel
GM8PZR