Low cost component tester - Page 1
Forum section: electronics / testgear

author: Nogtail
author_rank: Regular Contributor
timestamp: September 19, 2016, 04:18:14 pm
content: I have recently got myself some components from sites with a great reputation for selling repackaged/fake chips (AliExpress, eBay...) and realised I should probably get myself a component tester to sort the good from the bad. I can't seem to find any name brand component testers but have found a heap of low cost (less than $20.00 AUD) testers on eBay, seehttp://www.ebay.com.au/sch/i.html?_from=R40&_sacat=0&_nkw=transistor+tester&_pgn=3&_skc=100&rt=nc. I don't need anything particularly accurate, just trying to make sure I don't get a $0.02 MOSFET for $2.00.Are the eBay testers worth the money? Is it possible to find a tester from a more reputable manufacturer without breaking the bank?Sorry if this is in the wrong place or has already been asked, I am new here.

author: Falkra
author_rank: Regular Contributor
timestamp: September 19, 2016, 04:30:11 pm
content: Hi,Peak electronics has some nice testers, not so cheap, not so expensive, and realiable (imo).The DCA55 may be interesting for you (I have one).Here is the description from the manufacturer :http://peakelec.co.uk/acatalog/jz_instruments.htmlIf it is too cheap, you won't get accuracy and reliability.

author: TheBay
author_rank: Unknown
timestamp: September 19, 2016, 04:47:01 pm
content: Quote from: Nogtail on September 19, 2016, 04:18:14 pmI know this is a MEGA thread, but some really useful information in here and might be worth asking the question to see if any of these cheap ones can do what you are looking for.They work really well for the money, provided it does what you need.https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/

author: edavid
author_rank: Super Contributor
timestamp: September 19, 2016, 04:51:00 pm
content: Quote from: Nogtail on September 19, 2016, 04:18:14 pmThe "component tester" is definitely worth the money, but it won't help at all with the specific problem you mention of determining if a MOSFET has the right die inside the package. All it can tell you is that it's an N MOSFET and not e.g. a PNP.(The Peak tester mentioned above is no better for this purpose.)

author: Nogtail
author_rank: Regular Contributor
timestamp: September 19, 2016, 05:09:19 pm
content: Quote from: edavid on September 19, 2016, 04:51:00 pmI was hoping that I would be able to find fake/mislabeled chips if the values given by the component tester were significantly different to the datasheet.Do you know of any other ways to test for fake parts?

author: edavid
author_rank: Super Contributor
timestamp: September 19, 2016, 05:57:12 pm
content: Quote from: Nogtail on September 19, 2016, 05:09:19 pmFor MOSFETs, you really have to build a circuit that will test them at a high current, and see if the on resistance is reasonable, and that they don't overheat. If they pass that, you need to test them at rated voltage.All component testers are low current, low voltage devices, so they can't do this.

author: eKretz
author_rank: Frequent Contributor
timestamp: September 19, 2016, 06:19:47 pm
content: Other than a legit old school curve tracer like a Tek 576 anyway - but those don't usually come cheap. They are also somewhat time consuming to use. Best bet would be not to do your component shopping on eBay; failing that you'll just have to take the occasional (or not so occasional?) junk component and replace it when it doesn't do what is supposed to.

author: jonovid
author_rank: Super Contributor
timestamp: September 19, 2016, 06:46:55 pm
content: Chinese TesterQuoteI have a Chinese Transistor Tester Diode Triode inductor Capacitance. it works for me. calibrate test the tester's calibration on known values, before testing un-known values. ok -or+10% my tester fails at Capacitance under 45pf. also falls at inductor /resistor10 or lower. note- component type and mode of test is automatic. has pads for SMD components too. three pins or conductors 1,2,& or 3 do all the tests, 9v batt , the backlit screen shows supply voltage on boot up , transformers logo optimus Prime, ? what,, up-&-running the screen shows component type ,value & pin-out, automatic power off after 10sec of no testing - aliexpress

author: Jester
author_rank: Frequent Contributor
timestamp: September 20, 2016, 01:33:13 pm
content: Quote from: Nogtail on September 19, 2016, 04:18:14 pmI have one of these and for the money it's a very handy tool, it works surprisingly well.

author: glicos
author_rank: Regular Contributor
timestamp: September 20, 2016, 02:14:11 pm
content: If your a type of DIY'fers, the SEMTEST project of EPE magazine is probably the best. I think info regarding this project is on their 2013 issue

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: September 21, 2016, 03:17:49 am
content: The Chinese LCD component testers seem to work very well for bench use, especially when salvaging components. One small point- when you come to putting the tester in a case, remember to include a switch in the battery lead as the 9V battery does not last long with the unit off.I removed the ZIF socket and stood it on legs so that it projected through a hole cut in the clear plastic lid of a project box, with the LCD pressed against the inside of the lid.BT

author: Muxr
author_rank: Super Contributor
timestamp: September 21, 2016, 03:21:41 am
content: I second the chinese tester mentioned by others, I have two different versions of it. Both work surprisingly well.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: September 21, 2016, 05:03:17 am
content: Those testers work well for what they do. But they don't test a lot of things. Not breakdown voltage. Not gate capacitance. Not current handling capability. Not thermal resistance. And on and on.They do estimate ESR on capacitors. They measure resistance, inductance, capacitance and identify type and gain for 3 terminal active components. Those parameters will detect the very worst fakes, but a lot will get through.That said, I am glad I bought mine. Great value, and I use it often. Reliability is apparently OK. If have used mine literally hundreds (perhaps thousands) of times and it is going strong.