- Fake Chips - 2 Updates
- For those with Fluke Handheld DVMs - 2 Updates
| Tim Schwartz <tim@bristolnj.com>: Apr 04 08:58AM -0400 On 4/3/2016 7:25 PM, Cursitor Doom wrote: > but if mine burn up at say 1.3A, is that a clear indication that they're > fake? > Your thoughts, gentlemen.... Wherever possible I try to source parts from a reliable vendor. In the USA, that means (alphabetically) vendors like Allied, Digikey, Mouser or Newark. Companies that buy their parts from the original manufacturer. I don't mind spending a bit more for parts that I believe will be reliable, as I like avoiding reworks, and wondering if the problem was my diagnosis or the new part. Another theory I have is how subcontractors handle duds. Let's say a major optical laser maker subcontracts with "Dumb-Luck" electronics to make 10,000 CD player lasers (optical blocks) for them. Dumb-Luck knows they have to make 13,000 to come up with 10,000 that meet spec. They know they are SUPPOSED to destroy any others, but instead sell them as new "A" stock lasers. They look like real ones, because they are, they just don't meet spec or work at all, and we have no way of knowing. They think they are being good businessmen by getting money for their scrap. Regards, Tim Bristol Electronics |
| Jeff Liebermann <jeffl@cruzio.com>: Apr 04 08:35AM -0700 On Sun, 3 Apr 2016 23:25:16 -0000 (UTC), Cursitor Doom >Is there any reliable method for testing parts for authenticity? Not reliable, but you can get some clues: <http://www.aeri.com/counterfeit-electronic-component-detection/> <https://www.erai.com/CustomUploads/ca/wp/2009_3Detecting_Counterfeit_Electronic_Components.pdf> <http://incompliancemag.com/article/novel-approaches-for-the-detection-of-counterfeit-electronic-components/> Checking for differences in package features and labeling is what I use. It won't determine if the device is authentic, but will detect if there's something obviously wrong or suspicious. An acetone Q-Tip wipe is a good way to test the labeling. I'm not ready to buy an X-ray Fluorescence machine to check for material differences. >their datasheets? For example, the 317 is claimed to be good for 1.5A, >but if mine burn up at say 1.3A, is that a clear indication that they're >fake? Sure. Just build a test fixture for each part and see what it can do. For individual xsistors, a curve tracer might do. For your LM317, a load tester. That's fine for large quantities. However, if you just need a few parts for a repair job, such an approach is impractical. If you can't afford to buy from a reputable vendor, then I suggest you buy from two or more eBay vendors, in the hope that at least one of them might be functional. My luck with this method has been good, but not perfect. I recently needed some 7812CK (TO-3 package) regulators. I bought from two different eBay sources and received obvious counterfeits from both. I then reordered the real part from Mouser, which worked. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| Jeff Liebermann <jeffl@cruzio.com>: Apr 03 09:46AM -0700 >Glad my 8050A doesn't have batteries. Is it Option 1 and duz it work on AC? Mine wouldn't work on AC until I replaced the battery pack. Here's what's involved in running it without a battery and replacing the display with LED's: <http://www.eevblog.com/forum/repair/fluke-8050a-repair/> Or, if you don't mind overkill, here's another LED and a graphic display transplant: <http://vondervotteimittiss.com/belfry/?p=180> <http://vondervotteimittiss.com/belfry/?p=129> -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| "Michael A. Terrell" <mike.terrell@earthlink.net>: Apr 03 04:52PM -0400 > >"I wish the Fluke 8920/8921/8922 true RMS meters (20 > >MHz upper limit) were as easy to repair and calibrate." > Holy chit, 20 MHz ? I don't even want to know what those things cost. Typical used price is around $500. I have seen them sell for $50, untested. http://assets.fluke.com/manuals/8920A_21imeng0000.pdf |
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