LFS: JOY 7307 Multifunction Calibrator - Page 1
Forum section: electronics / general

author: leighcorrigall
author_rank: Frequent Contributor
timestamp: November 15, 2020, 03:24:10 pm
content: Hi Everyone,In the process of looking around for an 8.5 digit multimeter, I came across this strange instrument an eBay seller was using to demonstrate specifications.eBay auction: #https://www.ebay.ph/itm/JOY-7307-Multifunction-Calibrator-/313106853782There appears to be a multimeter model from the same designer, which appears in the sale pictures.Does anyone have information about these? I am curious about their performance.Regards.

author: toastedcrumpets
author_rank: Regular Contributor
timestamp: November 15, 2020, 03:48:05 pm
content: That's fascinating. At £2k it's too much to take a punt on, especially from a seller with zero feedback and out of Singapore.I've tried Google Singapore but this didn't seem to give me specific results. Looking forward to hearing what people can dig up!

author: coromonadalix
author_rank: Super Contributor
timestamp: November 15, 2020, 06:40:30 pm
content: I would not use this in a certified lab or anything who need nist certifications / calibrations or precision stuffAnd yes its too pricey

author: alm
author_rank: Super Contributor
timestamp: November 15, 2020, 09:43:08 pm
content: Interesting that a small company is designing something like this. Keep in mind that the ranges are fairly limited (1V/10V, 1mA/100mA and resistors from 10 Ohm - 100 MOhm with zero specs (in that eBay listing, anyhow). So they could be simple metal film resistors for all we know. The specs that they give for the DCV / DCI ranges look nice, but they are missing critical specs like short-term and long-term stability, noise, etc. The specs are way too limited for me to drop $2600 on something in a laser-cut acrylic enclosure.Also keep in mind that the seller does not accept PayPal, so if you don't get the calibrator, or if it's not as described, good luck getting money back!

author: guenthert
author_rank: Frequent Contributor
timestamp: November 15, 2020, 11:39:31 pm
content: Somehow the URL got mangled above. I supposehttps://www.ebay.ph/itm/JOY-7307-Multifunction-Calibrator-/313106853782?ViewItem=&item=https://www.ebay.ph/itm/JOY-7307-Multifunction-Calibrator-/313106853782is the article in question.They seem to completely miss the point of calibration though, as the interval for which one can expect the device to yield the specified values isn't given. As it stands, one would be pretty silly to drop thousands on such a project, well made as it might be.

author: toastedcrumpets
author_rank: Regular Contributor
timestamp: November 15, 2020, 11:49:04 pm
content: Yeah the fascinating thing here is that its a new design and its really interesting to hear how close they've gotten to the advertised specs (and how). No one is going to use this in a cal lab without testing and verification of its performance specifications (and the time span over which these apply), but the fact that a new design has appeared is exciting.

author: Golds
author_rank: Contributor
timestamp: November 16, 2020, 03:49:49 am
content: I'm late,the link has expired

author: coromonadalix
author_rank: Super Contributor
timestamp: November 16, 2020, 05:21:40 am
content: search the joy 7307 .... calibrator and other ebay links appear and another website toohttps://www.ebay.ph/itm/JOY-7307-Multifunction-Calibrator-/313106853782https://www.ebay.com.sg/itm/JOY-7307-Multifunction-Calibrator/313106853782the same item number is shown lollJOY 7307 Multifunction Calibrator. Condition is New. Shipped with Non standard mailDcv10v :10uv-11v INL<1ppm, Tc <0.3ppm1v:0uv-1.1v INL<1ppm, Tc<1ppmDci100ma:0-110ma INL <2ppm , Tc<3ppm1 ma :0-1.1ma INL <2ppm , Tc<2ppmΩ：0RΩ 10RΩ 100RΩ 1KΩ 10KΩ 100KΩ 1MΩ 10MΩ 100M Ω

author: toastedcrumpets
author_rank: Regular Contributor
timestamp: November 16, 2020, 02:41:53 pm
content: You're right it's comes up on Carousel.sg herehttps://www.carousell.sg/p/joy-7307-multifunction-calibrator-1007081430/That even has a what's app number to chat to the seller. If you look at his other items he has that 6.5 digit multimeter plus a load of advantest 8.5 digit meters for sale. This looks like the developer.Google translate gives this slightly more detailed spec from the carousel page.FeaturesMEAS:DC voltage measurement, range 0-12.5v, resolution 7.5 bits, INL<1ppm after compensation, default filter mode.DCV:10V file, adjustable range -10uv~11v, resolution 7.5 bits, INL＜1ppm, Tc＜0.3ppm1V file, adjustable range 0uv~1.1v, resolution 7.5 bits, INL＜1ppm, Tc＜1ppmDCI:100mA gear: adjustable range 0~110mA, resolution 6.5 digits, INL＜10ppm, Tc＜3ppm1mA gear: adjustable range 0~1.1mA, resolution 6.5 digits, INL＜10ppm, Tc＜2ppmΩ:Fixed physical resistance output, a total of 9 levels: 0R, 10R, 100R, 1k, 10k, 100k, 1M, 10M, 100M. Each index is related to the resistance performance used. The calibration value is 7.5 digits display.Power: Power on/off button, long press for 2 seconds to turn on, then long press for 2 seconds to turn offMeas: DC measurement modeDc.V: DC voltage output mode, use shift+up and down keys to switch gearsDc.I: DC current output mode, use shift+up and down keys to switch gearsΩ: physical resistance output mode, directly use the up and down keys to switch gearsTC: No functionG.NULL: Guard switch. shift+null is the measurement mode return to 0EXIT.B: Menu exit key. Shift+B turns on and off BluetoothSHFIT: Multi-function keyM.AUTO: Menu. Shift+auto is automatic range conversion<: cursor to the left>: cursor to the right︿: number increase﹀: the number decreasesOK.OUT: Menu confirmation key. Shfit+OUT, output on and off

author: ass20
author_rank: Regular Contributor
timestamp: January 03, 2021, 10:16:38 am
content: i found video on youtubefor more info see qq join QQ group 384456070but i cann not register in QQ (qq close registration out side of china)and you can found another video in bilibili.com