Fake Tektronix probes (P6139B) circulating on the market? - Page 1
Forum section: electronics / testgear

author: martinot
author_rank: Regular Contributor
timestamp: August 03, 2020, 04:13:31 pm
content: Wanted some better 10x fixed probes (with higher quality leads and without the 1/10x switch) and bought some new Tektronix P6139B on eBay.Bought one single probe (complete with accessories new in plastic antistatic bag) from France and two probes (pair in a new complete unopened box with accessories ) from US. The strange thing is that they seem to be slightly different coming from the US reseller respectively from the EU reseller, even if they are supposed to be the exact same model.Maybe it was not such a good idea to bid/buy on eBay. I know you risk getting fake products. But both sellers seemed to be genuine companies and electronics resellers with great ratings. And if you find fake Tektronix probes on eBay, you might also risk to get them on other markets.The question is; which of the P6139B probes are probably genuine (if any), and which might be fakes (if any)?

author: tooki
author_rank: Super Contributor
timestamp: August 03, 2020, 05:14:28 pm
content: Is this a joke? One of those sets of "find the differences" pictures in a magazine?Literally the only difference after looking at the pix (since you didn't point outanything, nor lay them side by side for easy comparison) is the blue probe not having "Tek" between the point and the ground lead (which, for all we know, is just printed on the other side).

author: bdunham7
author_rank: Super Contributor
timestamp: August 03, 2020, 05:39:09 pm
content: Not to be snarky, but IMO they are all fake. Even if you went to Beaverton and got them directly from Tektronix, they'd still be fakes. There's a long story here which I won't repeat because I can't verify it, but they may be 'genuine fakes' which are made in the same manner and perhaps in the same factory as the so-called genuine ones, but are snuck out the door and sold through non-Tek channels.The clones can be pretty good. And you should performance test your probes yourself anyway. I prefer genuine clones to genuine fakes.https://www.ebay.com/itm/P6500-Oscilloscope-Probe-X1-X10-500MHz-Alligator-Clip-Test-Probe-For-TektronixHP/132299233288?hash=item1ecda61808:g:8Y8AAOSwcgZZlmW2

author: wraper
author_rank: Unknown
timestamp: August 03, 2020, 05:46:35 pm
content: Quote from: bdunham7 on August 03, 2020, 05:39:09 pmSorry but but did you read your own BS? How can you buy directly from Tek and bypass official Tek channels simultaneously?QuoteI guess it's the same bullshit story told just about any counterfeit crap. That it's made by a ghost shift at the same factory... bla...bla.

author: CDaniel
author_rank: Frequent Contributor
timestamp: August 03, 2020, 06:02:32 pm
content: A fake product is inferior , in this case bandwidth and overall quality , not made in the same factory and sold on the streetThat cheap chinese clone on ebay has for sure much lower specs than the original probe.

author: bdunham7
author_rank: Super Contributor
timestamp: August 03, 2020, 06:11:34 pm
content: Quote from: CDaniel on August 03, 2020, 06:02:32 pmThere's no law of the universe that says fakes have to be inferior. They just usually are.QuoteThen those differences will be readily apparent upon inspection and testing. Are they?

author: wraper
author_rank: Unknown
timestamp: August 03, 2020, 06:19:15 pm
content: Probes likely to be NOS with significantly different production date. Such injection mold changes are not rare. As of heatshrink tube, it's simply a heatshrink marking which has nothing to do with probe. What text you see (or don't see) on heatshrink simply depends on what piece of it happened to be used for particular probe. Not to say that heatshrink used in particular batch may have no marking at all.

author: jjoonathan
author_rank: Frequent Contributor
timestamp: August 03, 2020, 06:22:48 pm
content: I used to have a set of these before I switched to a set of PMKs. The frequency response was respectable! They had lots of imperfections, though: the stamped hook was too wide, sharp, and rusted, the BNC adapter was easy to situate such that the ground contact was broken but it looked fully plugged in, the probe condoms didn't match their specification and didn't go to fine enough pitch, and the adjustment pots were full of flaky burnt resin. I think there were a couple of accessories I wanted that they didn't have, too. All of these problems would have been livable, but when PMKs showed up reasonably priced on ebay I jumped.https://photos.app.goo.gl/R1NrvMkb82hEdiqF8

author: wraper
author_rank: Unknown
timestamp: August 03, 2020, 06:23:06 pm
content: Quote from: bdunham7 on August 03, 2020, 06:11:34 pmEven without measuring, it's marking says 1.5 times higher input capacitance. Also cheap probe measurements I've seen have shown they usually are piss-poor.

author: bdunham7
author_rank: Super Contributor
timestamp: August 03, 2020, 06:30:37 pm
content: Quote from: wraper on August 03, 2020, 05:46:35 pmSubtleties seem to be lost on you, perhaps lost in translation somewhere? When TEK (or any company) rebadges another company's product and resells it at a 1000% markup, I think of that as tantamount to counterfeiting, especially when that product is then sold as either a long-standing model or its successor. Yes, it's through official channels and it is their brand, but in my view I'm not getting what I'm paying for. The situation with the probes is not exactly that, but Tek's business practices here are borderline predatory in my view.QuoteI'm not trying to sell you a counterfeit probe. The one I linked to is an entirely different matter. However, the phenomenon of 'ghost production' that you dismiss as 'bla bla' is a very real thing and has been one of the main hazards of outsourcing your manufacturing to a Chinese partner.

author: Elasia
author_rank: Frequent Contributor
timestamp: August 03, 2020, 06:37:48 pm
content: When the chinese government promotes copycating... thats what you get.. just look at aliexpress or the like lolIf you have a good eye you can usually figure out its highly likely the same plant so getting it 3rd channel is not such a bad dealJust comes down to how profitable something is and if its worth their time to make a 'good enough' copy of it for cheap that sells.. even they are still bound to cheap fast good.. but if those three are satisfied and a mfg is just exploiting the market with a huge margin? look out below

author: wraper
author_rank: Unknown
timestamp: August 03, 2020, 06:39:53 pm
content: Quote from: bdunham7 on August 03, 2020, 06:30:37 pmIt may be real in 1 in 10000 cases or less but such claims made just about any counterfeit crap you see.QuoteRebadges are not something rare. But link you provided obviously is not for the same probe made at the same factory. Also price increase in such cases usually is not not 1000% but more like 1.5-3 times. Also if the probe was designed by Tek to begin with, obviously there will not be such probe sold under another brand.

author: bdunham7
author_rank: Super Contributor
timestamp: August 03, 2020, 06:40:45 pm
content: Quote from: wraper on August 03, 2020, 06:23:06 pmWell, that's 'readily apparent' is it not?I don't have this probe. However, my non-fake Chinese probes sold as such have actually been very good and spot on--and they were not $5/pair either. I'm sure there are reliable sellers and manufacturers and those that are not so reliable, just like everywhere else.

author: wraper
author_rank: Unknown
timestamp: August 03, 2020, 06:43:36 pm
content: Quote from: bdunham7 on August 03, 2020, 06:40:45 pmWhat do you laugh about? Original probe has 8 pf capacitance marking, knockoff has 12pF? Or do you imply that knockoff manufacturer is so humble that is more conservative with claims than Tek?

author: martinot
author_rank: Regular Contributor
timestamp: August 03, 2020, 06:46:18 pm
content: Quote from: tooki on August 03, 2020, 05:14:28 pmSorry, should have done that (obviously). Good point, thanks!Yes, the blue ring version (US) totally lacks the "Tek" embossment on the handle between point and ground lead.I attach two edited images with the differences that I have spotted (so far) pointed out:

author: bdunham7
author_rank: Super Contributor
timestamp: August 03, 2020, 06:50:08 pm
content: Quote from: wraper on August 03, 2020, 06:39:53 pmSorry if that wasn't clear--I did not intend to imply that the probe I linked was made at the same factory. I have no idea. The transfer and copying of IP and designs has so many combinations and permutations that I have no way of knowing the particulars. Perhaps the probe is made at a small factory two miles down from the Tektronix subcontractor and owned by the cousin of a worker at the Tek factory who lets him borrow the mold tooling on weekends. Or 500 miles away and owned by the brother-in-law of the assistant draftsman who sent him a copy of the mechanical design files.Markups and transfer pricing have a lot more variability than anyone knows. 1000% for accessories and small items is not at all unusual.

author: wraper
author_rank: Unknown
timestamp: August 03, 2020, 06:56:40 pm
content: So what?https://iq.ul.com/ul/cert.aspx?ULID=102778291

author: martinot
author_rank: Regular Contributor
timestamp: August 03, 2020, 07:01:56 pm
content: Quote from: wraper on August 03, 2020, 06:56:40 pmAny one who can firm the usage of this heat shrink tube on genuine P6139B probes (the EU version could be the fake one, or both, or none)?

author: bdunham7
author_rank: Super Contributor
timestamp: August 03, 2020, 07:03:44 pm
content: Quote from: martinot on August 03, 2020, 06:46:18 pmI don't think a counterfeiter would do that good of a job and then either miss or add the extra 'Tek' logo. My best guess is that both are official product and perhaps one or the other is NOS, perhaps the non-logo US ones. I found this image that comes from a test lab/reseller that would not likelyknowinglytraffic in counterfeits.

author: wraper
author_rank: Unknown
timestamp: August 03, 2020, 07:10:07 pm
content: Quote from: martinot on August 03, 2020, 07:01:56 pmDo you understand that on different batches they may use heatshrink from different suppliers? It's not a single source thing. Also as I already said it depends on what piece of heatshrink it was. It's not like they are printed with no gaps in text. If you zoom in photo in the datasheet, there is some text on the heatshrink.http://www.farnell.com/datasheets/2238523.pdf?_ga=2.20917560.1862341019.1596481585-1112704206.1581825782And no text on either side of it herehttps://uk.rs-online.com/web/p/oscilloscope-probes/7256604/

author: martinot
author_rank: Regular Contributor
timestamp: August 03, 2020, 07:19:32 pm
content: Quote from: wraper on August 03, 2020, 07:10:07 pmYes, the gaps are understandable. I also agree that they might source from several vendors. Just hoped if it might give some clue in one direction, or another (even if possibly a very long shot).

author: martinot
author_rank: Regular Contributor
timestamp: August 03, 2020, 07:25:53 pm
content: Quote from: bdunham7 on August 03, 2020, 07:03:44 pmYes, they where all new, but NOS as you say. Might still be NOS produced att different years.The US bought version (they are all produced in China) without logo on lower handle part was produced in 2013. Se attached images of the box it came in.

author: tooki
author_rank: Super Contributor
timestamp: August 03, 2020, 07:54:14 pm
content: Quote from: martinot on August 03, 2020, 07:25:53 pmSo... the locally-bought one is new stock (the new Tek logo only debuted in 2016), and the US-bought one is 2013 NOS, and you’re surprised the older one doesn’t have the logo on it that wouldn’t debut for another 3 years?All we have here was that at some point after 2016, Tek decided to put the new logo on the probe. That’s all.The “difference” of the heat shrink is no difference - heat shrink isn’t printed continuously, just in regular intervals.