6x lab standard precision resistors - Page 1
Forum section: electronics / general

author: Jester
author_rank: Frequent Contributor
timestamp: May 03, 2023, 09:34:28 pm
content: Can anyone venture a guess as to what these six resistors are worth?I'm going to put them on eBay and want to list them for a fair price.Much appreciated.

author: TUMEMBER
author_rank: Regular Contributor
timestamp: May 04, 2023, 09:14:31 am
content: It depends on what evidence of "quality" of these resistors you have. Do you have valid calibration certificates for each of them? Do you have a high-class meter with which you measured each of them in reference conditions? Their status is currently "unknown". You can ask for a high price, but you will not find a willing buyer. These types of resistors are quite popular on ebay. Prices from $250 are not unusual. But they generally have some known "life history" - generally "news from the factory are sold out".Take a look at how others offer and how they document the quality of their items.https://www.ebay.pl/itm/225505308948?hash=item348129f114:g:U~8AAOSwpKRkJ0kY&amdata=enc%3AAQAIAAAAwBJ7Bhfd2MiNUYV6LKJcVqctIjgb0wBtxddiK7Wx82fchl1xxNZkjtS6qtLZwydu2GLgJLotnB%2Ft4oLyRuMvq7xg5dSObLNXLY9FHiI0zcELlhwVgnIiGlpf2mh98HQKEE4yAr9W1%2FupLd51sdeh80U4H5BUt%2FqlpmfKl0BMg4LMuhiSgSBYif6Zh9OxpXff7H%2BW8zqNS6Sj%2F4nnotopTlpQcFk98w414HS316HGbs5dShVB6twtvgrp%2F%2FRSBGbZ5g%3D%3D%7Ctkp%3ABk9SR9ij1N78YQhttps://www.ebay.pl/itm/271930151419?hash=item3f504cd1fb:g:X8oAAOSwLVZVpZVU&amdata=enc%3AAQAIAAAA4C5y63oc%2BveuZVsLZbtqOTrTm%2F9kqA2oMHonR0YKiskYe2dD8liSu82SfxzXK9J6Tbpiyem2319r4llTMuLjpzDIiXZMwGibhaxGj4u6vdugLBFmA%2F8BqIvQ67xRzim25xE%2FHwiXoSaUbnPaF6ui6QNf1S8aktsCSMwlgxT6wCnLiPfZXyYO8c5eht3oQv0RNd4E7KJAF%2FPsg4VHJI2WD%2FEC2ZGzv85lIVt%2BborpaDuEa6F7w0VdMcw0f8tgJLTaMswntTtSABXf%2F6ljHdRVdzDRC9KwEDOEVl8wRGCyiq9i%7Ctkp%3ABFBM_uGo3_xhhttps://www.ebay.pl/sch/92074/i.html?_from=R40&_nkw=standard++resistors&LH_TitleDesc=0&LH_PrefLoc=2

author: Arhigos
author_rank: Regular Contributor
timestamp: May 04, 2023, 10:22:18 am
content: Old USSSR garbage, pretty much useless for today.Typical cost would be between $20- $100 for each one.

author: manganin
author_rank: Regular Contributor
timestamp: May 04, 2023, 10:49:21 am
content: Condition, condition, condition.Quote from: manganin on July 09, 2021, 09:51:57 am

author: Jester
author_rank: Frequent Contributor
timestamp: May 04, 2023, 04:04:17 pm
content: Quote from: TUMEMBER on May 04, 2023, 09:14:31 amUnfortunately I don't have any documentation, I was told they were surplus from NRC Canada. I guess I will price low and see what happens.

author: guenthert
author_rank: Frequent Contributor
timestamp: May 04, 2023, 04:25:49 pm
content: Quote from: TUMEMBER on May 04, 2023, 09:14:31 amWell the $250 (asking price) for the ones from Ukraine were for a set of 3 (looks like a good deal to me). The one for 6000 sloty (Poland isn't using Euro?) is a Tinsley (originally made for a 5ppm match, compared to the 100ppm for the soviet ones).I doubt metrology labs are buying from random sellers on the secondary market (I'd guess they might buy a competing lab's equipment when that goes out of business).Such resistors are made for operation in an oil or air bath as they tend to have a fairly high temperature coefficient (they are optimized rather for long time stability). Only the most affluent or dedicated hobbyist (some of which you find here) have access to those.Tip: characterize those resistors yourself and publish your findings here. That sure helps charging a premium.

author: TUMEMBER
author_rank: Regular Contributor
timestamp: May 04, 2023, 04:51:35 pm
content: Yes, you're right Poland has (still) its own currency, Polish Zloty. Despite the fact that we are "economically associated" in the EU. And one more thing - these resistors are Russian because they were produced in the USSR. Do you think Texas is an independent Country? Such a "country" at that time was the Ukrainian REPUBLIC - it did not have an independent statehood. By the way, Russian resistors in "good classes" did not significantly differ from the "western ones". They weren't just as accessible, hyped up and exorbitantly expensive as...the physics and materials they are made of are the same everywhere.Sorry, the text was created with the help of google translate. It certainly only partially reflects what I wanted to convey.

author: Jester
author_rank: Frequent Contributor
timestamp: May 04, 2023, 08:54:36 pm
content: The guy stated they were used in an oil bath.I have no idea what type of meter or bridge they used to measure the value in the second image, but that is a lot of digits and way way beyond my 6.5 digit Agilents resolution. Obviously NRC would have some pretty crazy metrology equipment. We actually live a stone throw from the sprawling main headquarters complex and a builder wanted to build a condo about 1km away that would require blasting for the excavation, apparently the condo project got nixed because of the potential effects from the vibrations on some of NRCs sensitive equipment.

author: czgut
author_rank: Contributor
timestamp: June 26, 2023, 03:56:52 am
content: This resistors are made of Manganin. That means that temperature coefficients will be between -10ppm/deg and +12 ppm/deg in 18°C ..30°C range. (ppm = part per million =0.0001%)Moreover they exhibit thermal hysteresis (R(T) cooling curve may be several ppm apart from heating R(T) curve) when cycling form 18°C to 28°C.They usually fulfill 0.01% specification, but to get more from them You would need to keep them in constant temperature bath (probably in NCR they were used this way).

author: Nanitamuscen
author_rank: Contributor
timestamp: June 26, 2023, 04:07:29 pm
content: Resistance coils p331, p321, p310 are measured relative to standards of a class higher in oil thermostats. They can also be used without thermostating, but in a composition with a thermometer and a resistance table, taking into account the temperature coefficients that are indicated in the passport of each resistance coil.A typical thermostat for these resistances can be seen in the attachments.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: June 27, 2023, 07:29:21 pm
content: TUMEMBER has a point, but using Texas as an example for his point is probably not the best example ( or, on second thought. may it is). In the past, Texans frequently seemed to regard Texas as ALMOST another country, since at one time it was a country on it's own.I think this frame of thought has changed recently with so many new residents in Texas.I realize the history of Ukraine and the relationship with Rus is different and far older than history of Texas with the rest of the US.However I know just enough about Eastern European History to know that I do not really know anything.

author: EC8010
author_rank: Frequent Contributor
timestamp: July 16, 2023, 04:02:32 pm
content: This morning, I bought six very similar resistors (0.1, 1, 10, 100, 1k, 10k) made by Cambridge Instruments (UK) at an amateur radio rally for £85 the lot. I've just tested them (fortuitously, the lab was at 20C) and they agreed sufficiently closely with my 34470A 7 digit DMM that I probably believe the enormous resistors' calibration values (1987!) rather than the meter - which must have much smaller resistors. I told my wife that these resistors normally live in a temperature-controlled oil bath, "I hope you're not going to do that here." Ithinkthat means an oil bath has been vetoed for the moment.

author: alm
author_rank: Super Contributor
timestamp: July 16, 2023, 04:19:51 pm
content: Quote from: EC8010 on July 16, 2023, 04:02:32 pmif the look very similar, then they may well be USSR-made that were rebadged by Cambridge Instruments. I have a R4030 resistance standard that was made in the USSR but branded "Time Electronics".

author: EC8010
author_rank: Frequent Contributor
timestamp: July 16, 2023, 06:02:28 pm
content: What I really meant was that they were large and cylindrical. Mine are about the size of a 500g treacle tin (and oil-filled). But they have enormous solid copper cow horn handle bars coming out the top with a pair of screw terminals at the ends to make the four wire connection.

author: alm
author_rank: Super Contributor
timestamp: July 16, 2023, 07:13:13 pm
content: Quote from: EC8010 on July 16, 2023, 06:02:28 pmTry looking for information about Leeds & Northrup 40xx series resistor, or Rosa / NBS type resistors. These likely are fairly similar. I would suggesting opening a new topic in the metrology section if you have any questions about them, since they will have very little in common with the resistors that this topic is about.