Garage sale metrology haul - Page 1
Forum section: electronics / general

author: golf32
author_rank: Regular Contributor
timestamp: August 28, 2021, 09:07:12 pm
content: Just got back from the coolest garage sale I've ever been to. I'm just getting started in DIY metrology so I am really excited. There was lots more stuff that I regret not buying, but hey, gotta leave something for everyone else.Fluke 732A DC reference standardFluke 5450A resistance calibratorRacal-Dana 9475 rubidium frequency standardAzonix thermocouple readerThe best part is:All of this was $80!Refurbishment, teardowns, calibration, and measurements soon to come.

author: bob91343
author_rank: Super Contributor
timestamp: August 28, 2021, 09:17:59 pm
content: Fantastic! I wish I had been there. Where is this stuff?

author: TiN
author_rank: Super Contributor
timestamp: August 28, 2021, 09:26:21 pm
content: Welcome to ppm OCD.It's $80 now, but will be hundreds later

author: TheSteve
author_rank: Unknown
timestamp: August 28, 2021, 09:27:36 pm
content: We're all wondering why you left anything behind!

author: golf32
author_rank: Regular Contributor
timestamp: August 28, 2021, 10:59:20 pm
content: California bay area, though it's probably over by now. Lots of stuff that used to be owned by a guy who worked at UC Berkeley.

author: golf32
author_rank: Regular Contributor
timestamp: August 28, 2021, 11:01:22 pm
content: Already looking at what I have to do, it is looking expensive.New SLA batteries, replacement parts, shipping, calibration.I'm looking into ways for cheap and easy calibration. I'm talking with my university lab manager and some EE friends at other universities.

author: guenthert
author_rank: Frequent Contributor
timestamp: August 28, 2021, 11:04:23 pm
content: Quote from: golf32 on August 28, 2021, 10:59:20 pmI'm just going to pretend I didn't read that.

author: TheDefpom
author_rank: Frequent Contributor
timestamp: August 28, 2021, 11:57:55 pm
content: WOW that is a VERY nice score, I am so envious ! (especially for the 732A).The 5450A probably has dirty relay contacts, at least mine did when I got it, I found that by removing the relays and exercising them on an oscillator for about 30 seconds each did the trick, I only had 1 relay that I had to replace as it was sticking, luckily I was able to find one at the time.I did a video on it, you can find it here:

author: golf32
author_rank: Regular Contributor
timestamp: August 29, 2021, 12:12:17 am
content: That explains why most ranges read slightly high. I will have to try that, Thanks.

author: TheDefpom
author_rank: Frequent Contributor
timestamp: August 29, 2021, 12:16:32 am
content: How I could tell it was an issue on my unit was I would switch in and out of a resistance selection, if the reading is different every time, or changes during that test, you can tell it is not repeatable, and in that case it is a bad relay, when I was doing that test I could actually see some of the readings gradually getting better and better, also if possible use 4 wire mode, the 2 wire is just using a known offset based on a cable that was used with it in the past, so cant be trusted.

author: 1audio
author_rank: Frequent Contributor
timestamp: August 29, 2021, 04:24:20 am
content: I also have an ex-UC Berkeley 732A. Another prof was unloading some stuff at a local surplus store 10 years ago. I also got an HP 5370 in that haul.I have been through the refurbish experience. Its not that bad. New gel cells. Possibly some new electrolytics. A few minor mods to the battery case to use more reasonable batteries and check the charging current. I'm probably local to you in the east bay if you find you need local "support" for your new addiction. Feel free to PM me. It can get pretty bad. However if you have access to things like KVD's you don't need to own them. You won't be using them daily.

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: August 29, 2021, 11:35:36 pm
content: Nice haul. Your aquisition almost qualifies you for the TEA crew. But your attitude doesn't. We don't tend to leave anything behind.

author: TheDefpom
author_rank: Frequent Contributor
timestamp: August 29, 2021, 11:57:29 pm
content: Yes, leaving stuff behind really threw me.... I just don't understand how that could be done.

author: golf32
author_rank: Regular Contributor
timestamp: August 30, 2021, 07:52:53 pm
content: It was mostly older, lower spec equipment that I left. I definitely got the best stuff. Kicking myself right now for not picking up the null meter, but hey, I have my hands full with gear at the moment anyway...

author: golf32
author_rank: Regular Contributor
timestamp: August 30, 2021, 07:58:38 pm
content: I'm definitely going to make sure to document all the repairs, calibration, etc. I already have parts coming in for the 732A.I hear that I should let it burn in for a while before having it calibrated. It probably hasn't been turned on for a while. Anyone have any clues as to how long?

author: TiN
author_rank: Super Contributor
timestamp: August 30, 2021, 10:28:07 pm
content: Few years sounds about right for 732A. Be sure to find lab within driving distance as battery life of 732A is quite short (you do want to have 732A hot at all times, including shipping/transport time to preserve previous ppms).