[volt-nuts] Short term "standard" cell?

[m k]

On 12/03/17 17:27, Dr. David Kirkby (Kirkby Microwave Ltd) wrote:
> On Sun, 12 Mar 2017 at 17:03, Frank Stellmach <frank.stellmach at freenet.de>
> wrote:
>
>> Hi Chris,
>>
>>
>>
>> Therefore,  instead of poking around with these mediocre 10V
>> "references", I'd look for a possibility to get access to a 3458A, maybe
>> there's a friendly volt-nuts nearby.
>>
>> Frank
>>
> There are a number of reference boards supposedly removed from 3458As on
> eBay. Assuming they are non counterfeit (not necessarily a valid assumption
> for items on eBay), how easy would they be to integrate into a box to make
> a stable reference?
>
> The LTZ1000A chip is about $50 new, but to make a stable reference you need
> quite expensive resistors, so a used 3458A reference is attractive. But I
> don't know if problems making low thermal EMF joints might totally ruin the
> potential performance.
>
>
>
>
The suspicion is that they may be genuine, but were rejects because of noise bursts. I bought one a while ago, but still not sure of its long term 
stability.