Resistors Used in an LM399 Circuit

[Chance92]

I found a reference circuit in an old Valhalla 4300B micro-ohm meter. I wonder what type of resistors these are? Do they have low temp coefficients?

[Grandchuck]

I will guess that they are wire wound.

[Edwin G. Pettis]

That is easy to answer, we made those for Valhalla, back in the early '80s, we went by the name GoldStar Resistors then, we made all of their resistors....note the same yellow cases as Ultrohm Plus uses (when available).  They have the same specs as Ultrohm Plus, TCR of 0±3PPM/°C.  Of course they are precision wire wound resistors.

[TiN]

Spider webs and strategically tilted LM399, -10 ppms to performance 

[Chance92]

That is easy to answer, we made those for Valhalla, back in the early '80s, we went by the name GoldStar Resistors then, we made all of their resistors....note the same yellow cases as Ultrohm Plus uses (when available).  They have the same specs as Ultrohm Plus, TCR of 0±3PPM/°C.  Of course they are precision wire wound resistors.

Wow! Thank you for the info. I didn't expect someone from the manufacturer to answer my question. EEVblog is a magical place.

[Chance92]

Spider webs and strategically tilted LM399, -10 ppms to performance 

Precisely tilted to counter the uneven uneven air flow This is better than I expected to be honest, considering there's a cooling fan behind without any dust filter, and 20+ years of usage of course.

[cellularmitosis]

That is easy to answer, we made those for Valhalla, back in the early '80s, we went by the name GoldStar Resistors then , we made all of their resistors....note the same yellow cases as Ultrohm Plus uses (when available).  They have the same specs as Ultrohm Plus, TCR of 0±3PPM/°C.  Of course they are precision wire wound resistors.

Wow! Thank you for the info. I didn't expect someone from the manufacturer to answer my question. EEVblog is a magical place.

FYI he still manufactures them, and they are very affordable, should you happen to get bitten by the volt-but bug