I want to make an LCR meter  - Page 1
Forum section: electronics / testgear

author: thannara123
author_rank: Newbie
timestamp: January 03, 2015, 04:44:04 pm
content: Hello experts I want to make an inductance ,capacitance & Resistance meter ?what is the principle behind each one ?any reference design ?thanks in adance

author: JoeO
author_rank: Frequent Contributor
timestamp: January 03, 2015, 06:32:19 pm
content: Google is your friend.

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 03, 2015, 06:38:58 pm
content: Check out this discussion (and the product discussed)...https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/The circuit is quite simple, and all the "magic" is done in the software.That is the way it is done here in the 21st century.But if you want to study the 19th century historical methods and gear, as JoeO suggests, Google (and Wikipedia, et.al.) will reveal enough information to keep you reading for months.

author: JoeO
author_rank: Frequent Contributor
timestamp: January 03, 2015, 09:05:33 pm
content: Quote from: Richard Crowley on January 03, 2015, 06:38:58 pmHe said he wanted to "make" one. You told him how to buy one.How is buying one or reading the forum going to explain the principle behind each one?Since when is a 328 based LCR meter a "reference design"?Is it too much for someone to at least do minimal research before coming on here and asking an open ended question?A poster should at least make a minimum attempt to research some topics for himself.

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 03, 2015, 10:45:23 pm
content: Quote from: JoeO on January 03, 2015, 09:05:33 pmNo. I did not suggest that he BUY anything. I suggested that the $20 circuit, software (which is open-source) and discussion would have potential benefit if he was researching how to build his own LCR meter.Based on popularity and novelty, I submit that the $20 LCRetc. meter IS a 21st century "reference design".Or do you think a "reference design" is something that is 100 years old and based on firebottles?Think outside the box. Perhaps the box is a different shape and larger size here in the 21st century.I also suggested that the old original concepts and circuits were also available by spending a few quality milliseconds with Google.

author: JoeO
author_rank: Frequent Contributor
timestamp: January 03, 2015, 11:16:18 pm
content: I see your point. But you don't learn much when you are a ham appliance operator, do you?

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 03, 2015, 11:40:03 pm
content: Quote from: JoeO on January 03, 2015, 11:16:18 pmOr any other kind of appliance operator, for that matter.Alas, that is a whole discussion about electronics in the 21st century. While remarkable advancement in technology and engineering have given us amazing things that were barely dreamed of a generation ago, they have also changed the landscape for what people can learn by DIY.I think it is a great benefit that Dave does teardowns of equipment ancient and modern to show people what is inside, how things work, and what some of the design decisions (and manufacturing techniques) may have influenced how gear is/was produced. But modern kids learning electronics aren't probing galena crystals anymore. They are blinking LEDs with Arduinos (et.al.).OTOH, certainly there is educational value in reviewing the fundamental technologies, those old LCR bridge instruments that are only found in museums anymore, etc.

author: parasole
author_rank: Contributor
timestamp: February 18, 2023, 07:17:19 am
content: Hello folks,sorry to resurect this old thread, to me it looks more suitable than creating a new topic...I was a happy DE5000 owner for almost 10 years, until did a dumb mistake to measure an in-circuit HV capThe result is as expected, destroed front end chip hence rendering my meter useless, unless some one will whant main chip which is alive.... I did try to contact both, DER and Cyrustec, no feedback from the later and DER recomended to buy new one, sad enough for such waste of resourses...Long story short, now I am looking what would be better, to get another DE5000 or DIY version, with current candidates being LCR2 or ether Elector 2013/2019 LCR...Then during my continuous search, I came across this neat piece of equipment which stand apart in terms of used component as being modern and relative low cost, it fit the bill nicely as still use bridge measurement hence have good accuracy. The question here if some one else have seen/build it and may share his/her experience?Any opinions?https://github.com/jankae/LCR

author: JohanH
author_rank: Frequent Contributor
timestamp: February 18, 2023, 08:40:27 am
content: Interesting.In the github issues, there is one person reporting that he can't get the touch display to work, because the touch chip has changed and the library doesn't work (for this person; reason is unknown).

author: coromonadalix
author_rank: Super Contributor
timestamp: February 18, 2023, 11:33:36 am
content: The big problems are always to integrate an discharge circuit in case of ... but people dont wait or dont do the proper discharge proceduressencore added this in some lcr's and a few other brand too, but not fast enough, can't wait yada yadayou blew up once and you remember afterwards .... i'm happy with an DE-5000 and believe me i short the cap'sfor a low price device just buy a new oneThe lcr 20$ project is very niceTons of discussions here, yeah >320 pages, but as written earlier, you can learn about it, i have an older model 2x16 lines ... but i say it is impressive and reliable, not perfect but, better than nothing ..... the idea of transistors / scr's / mosfets testing is marvelous,Since i'm getting older, it would need a bigger screen ...the previous thread project seems very interesting .... with an AD5941 for the front end, isolated supply and communication bus for this ic ....But It's a 3 year passed project, nothing new or added since ??The Elektor lcr kit at 700 euro .... if it's the 2Mhz model, is a very expensive model, and you may blow it up too, like many other models ...

author: parasole
author_rank: Contributor
timestamp: February 18, 2023, 12:03:04 pm
content: Quote from: JohanH on February 18, 2023, 08:40:27 amYeah, that is the list I would worry about, it is important the core function to work as expected...Quote from: coromonadalix on February 18, 2023, 11:33:36 amSure, now I know, lesson learnedQuote from: coromonadalix on February 18, 2023, 11:33:36 amActually if I go by this route, than probably I would not replicate it fully, important the source code is available and then perhaps I may simplify it a bit... I like the idea behind LCR2 of using ICL7135, while from 2Mhz Elector I like the use of DDS... all in all to use as many components which are available in my drawer... However I really like github/jankae LCR and perhaps will pull the trigger for it...

author: coromonadalix
author_rank: Super Contributor
timestamp: February 18, 2023, 12:13:51 pm
content: Not derailing the threadFor the elektor, you wont get the source code, just the compiled code to put in the mcu ... it would be too easy to copy china "cough" loll

author: kripton2035
author_rank: Super Contributor
timestamp: February 18, 2023, 12:32:16 pm
content: the elektor lcr meter from 2013 has the sources available here :https://www.elektormagazine.com/labs/500-ppm-lcr-meter-110758

author: coromonadalix
author_rank: Super Contributor
timestamp: February 18, 2023, 12:42:02 pm
content: oh it is now ...Elektor have the botloader and the lcr meter firmware HEX files

author: parasole
author_rank: Contributor
timestamp: February 18, 2023, 12:48:47 pm
content: Quote from: coromonadalix on February 18, 2023, 12:42:02 pmYes, it was mentioned some time ago in Elector dedicated thread that project become open source and all files were posted there...

author: TimFox
author_rank: Super Contributor
timestamp: February 18, 2023, 02:39:49 pm
content: There is a good application note from Hewlett Packard from the 1980's (IIRC) about the different ways to measure LCR.Another one specifically on what we now call a "LCR Meter" from IET (successor to General Radio):https://www.ietlabs.com/pdf/application_notes/030122%20IET%20LCR%20PRIMER%201st%20Edition.pdf