[volt-nuts] 3458A reference boards on ebay

[Frank Stellmach]

I forgot to mention, that these original hp reference are a bargain for 
around 100$.
LTZ1000 /A cost 35.. 55$, 3 PWW or MBF for 10..20$ each, plus the 
additional stuff.

They only need a thermal shield around the LTZ1000A on component and 
solder side, the pimping to 55°C (by 100k PWW in parallel to the 15k 
BMF), a shielding, and a PSU.

The circuit is the same as in the LT datasheet, that's totally 
sufficient for stability.
And it's very compact, easing the shielding.
No fancy slots or other gimmicks for the PCN and components..
The stability is determined mainly by the LTZ1000 and its oven temperature.

Therefore, that's a recommendation.

FRank