[volt-nuts] Reference Calibration Options - Solartron 7081andFluke 731B and 335A

[J. L. Trantham]

I have still not gotten the reply from AMTEK.  The questions I asked were 
for the details of the calibration (though I did not ask specifically about 
adjustment, just assumed that it was part of the calibration) and what 
services (primarily repair) and products (manuals, test cables, etc.) they 
had for the 7081.  As far as the 731B's and 335A go, I think I will wait on 
the 7081 to get back (assuming they are not just blowing me off) then 
measure the 731B's since Fluke offers no repair service.  If I read the 
manual correctly, I think I will have a chance of bringing them to spec 
myself.

The 335A seems to have another issue that I will explore over the weekend. 
There is about 5 mV of ripple on the output.  I think I am going to need to 
delve into the beast for a 'rebuild' with probable replacement of the power 
supply capacitors and perhaps others.  Since the cost of this calibration is 
the higher of the Fluke costs and the 'rep' on the beast per the list is 
'suboptimal', I think I will keep this 'inhouse' and rebuild and recalibrate 
myself, after I get the 7081 issue resolved.

Pending all the above, I may then send one of the 731B's in for an 
'official' Fluke calibration to act as a verification of the 7081.

I would surely like to add something like the 3458A to the collection but 
the price seems prohibitive.  For my needs, if I can get the 7081 cal'd, it 
will more than meet my needs.

Joe


----- Original Message ----- 
From: "gbusg" <gbusg at comcast.net>
To: "Discussion of precise voltage measurement" <volt-nuts at febo.com>
Sent: Friday, September 09, 2011 8:09 PM
Subject: Re: [volt-nuts] Reference Calibration Options - Solartron 
7081andFluke 731B and 335A


> Hi Joe,
>
> Another thing to ask AMTEK is whether or not their 7081 calibration always
> includes adjustment? Or do they only adjust if a parameter reaches a
> guardband limit or spec limit?
>
> Obviously for your purposes it would be nice if they adjusted the box back
> to nominal. But that's not a typical service for most T&M calibrations.
>
> The neat thing about the "golden" calibration (Loveland Standards Lab Cal)
> for Agilent's 3458A is that it *always* includes adjustment of the box 
> back
> to nominal. But that turns out to be more feasible in the case of the 
> 3458A
> because there are only 3 adjustments for the total DCV, DCA and ohms
> functions: CAL 0, CAL 10 and CAL 10k. (Note: This *always adjust" policy
> only applies to the "golden" 3458A cal, not for example the "silver" cal.)
>
> Let us know what you find out from AMTEK regarding their 7081 cal.
>
> Thanks,
> Greg