Resistors mean business when they have certificates
Added 2018-08-15 18:21:38 +0000 UTC5 months lead time and 200 bucks for these beauties! The metal can ones are hand-crafted and hermetically sealed. And that's only accessories in the quest for an ultra-stable voltage reference.
The total accuracy of around 0.01% is secondary, it's the low temperature coefficient of ± 0.05 ppm/°C that makes these so special.
https://xdevs.com/article/kx-ref/
Comments
I maintain a set of indexes of the questionable ebay resistors <a href="https://ssl.pepas.com/hifi/" rel="nofollow noopener" target="_blank">https://ssl.pepas.com/hifi/</a> no links unfortunately, so you have to copy and paste the description of the resistor into ebay search
Jason Pepas
2018-08-21 14:00:38 +0000 UTCYep, it's a voltage source that tries to change very little over temperature and time.
Marco Reps
2018-08-16 15:56:29 +0000 UTCSo from the linked article I gather that these are part of a reference voltage source to calibrate your instruments with?
Jan Ka
2018-08-16 14:07:48 +0000 UTCSome call em the greybeards ... <a href="https://xdevs.com/doc/xDevs.com/RBOX/rbox_r2_i.jpg" rel="nofollow noopener" target="_blank">https://xdevs.com/doc/xDevs.com/RBOX/rbox_r2_i.jpg</a>
Marco Reps
2018-08-16 06:03:46 +0000 UTCThanks for the box ;) If I ever CNC machine enclosures for the references, I'll send you one! But Aluminium is probably not going to be very good on it's own, needs another layer of thermal insulation without any electrical properties so that it can touch the kx board. Mineral wool?
Marco Reps
2018-08-16 05:57:17 +0000 UTCMe neither ... but it seems like a good idea to assemble the references and leave em turned on for however many years it takes to obtain a 3458 😂
Marco Reps
2018-08-16 05:49:13 +0000 UTCYep! There are some questionable but significantly cheaper sources on eBay <a href="https://www.ebay.com/itm/121032470224" rel="nofollow noopener" target="_blank">https://www.ebay.com/itm/121032470224</a>
Marco Reps
2018-08-16 05:42:57 +0000 UTCDid you order these direct from Vishay? I am playing with the double LM399 board from Xdevs because there was no way in hell to get the resistors for the LTZ. But i do have 2 spare double 399 boards from OSH park, if you are intersted.
Roger Koch
2018-08-16 00:52:50 +0000 UTCThis reminds me, I need to build one or two of the KX ref that I have boards and LTZs and most of the other parts. Still don't really have a better multimeter than an HP 3457A and an HP 3456A, but it might be fun.
Jamie Magin
2018-08-15 20:23:30 +0000 UTCI love that particular scene. Those original packings look good on video, I am glad :)
Holger P Kleinert
2018-08-15 19:16:08 +0000 UTCThey had their top resistor scientists on this!
John McCormick
2018-08-15 18:38:10 +0000 UTCAlso minor dog fight over the last squeaky toy that still squeaks ... no casualties!
Marco Reps
2018-08-15 18:23:05 +0000 UTC
