Fluke Credibility - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: September 30, 2010, 12:25:20 am
content: Check this out, from the blog comments:http://register.fluke.com/globalforms/goyellow/index.htmlPretty funny, but I think it means Fluke have to take this GSM phone thing seriously, because as it stands, that kind of advertising doesn't really have any credibility any more IMO.Dave.

author: PetrosA
author_rank: Frequent Contributor
timestamp: September 30, 2010, 12:57:52 am
content: It was thanks to that add that I won the Extech pencil DMM. All you had to do was find the Extech meter on Fluke's website. Easy as pieI agree though - they need to address issues as fast as ever if they want to stay top dog. The only good thing they have going with this issue is that it's not a life safety issue. They've had enough of them with their meters over the last few years.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: September 30, 2010, 02:00:05 am
content: They are back at the drawing desk , after 9 emails that we had exchange ... ( Greece -> Washington )They are looking to improve the 87-5 .And I gave them even more ideas about improving the 28II too.Like an crystal clear window at the batteries compartment , so to be easy to have an visual on the AA batteries ( leakage inspection ) .And my last suggestion would be " The instructions manual to have also the Greek language too " .My own case looks to had stuck , I think that they had send an new 87-5 for me by mistake (Holland - Greece) ,as I am expecting an 28II , and they try to cover up the mix-up , they will do that eventually ,but I will "enjoy" the extra delay !!

author: TopherTheME
author_rank: Regular Contributor
timestamp: September 30, 2010, 05:20:58 am
content: I'm sure Fluke will give the problem the attention it deserves as they are known for their solid customer service.When I worked as a lab aide, one of the techs left a 77 in an oven at 300C over night by mistake. The next morning we opened up the oven and there was this gray and yellow blob sitting in the oven. The meter was sent back to fluke as "defective" and they replaced it free of charge! They probably thought a new meter was worth the laugh.

author: EEVblog
author_rank: Unknown
timestamp: September 30, 2010, 07:10:30 am
content: Quote from: TopherTheME on September 30, 2010, 05:20:58 amI hope so, and would like to think so.But the cynical side of me can't help but think that Fluke are too big, and the 87V is too big a product, to actually get any sort or medium term response from them. So I think the most likely response is that they'll quietly fix it in the next version, whenever that comes out.Unlike Extech for example who jumped through hoops to acknowledge and redesign the RC100 meter when it blew up.They even offered to fly over to my lab and explain themselves in person!Albeit that was a much more serious issue than some GSM interference.Dave.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: September 30, 2010, 10:45:34 am
content: There is also an video link in that page ...http://assets.fluke.com/video-DMM/3821284A_pile-of-meters-video/3821284_pile_of_meters_640x360.htmlBut I do wonder Dave , how did you find this link ?, it does not look to be easy to locate it,with out some help of some one !!Well I have never register anything yet to Fluke , and probably this pages comes first at the registered owners .

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: September 30, 2010, 11:33:32 am
content: Just found this link , that added to me only confusion ...Who leads who ? who builds what ? who does the R&D ?http://www.danaher.com/business/strategic_detail.asp?key=82)An picture found In a Fluke PDF document..http://support.fluke.com/find-sales/download/asset/2138394_a_w.pdf

author: Waifian
author_rank: Regular Contributor
timestamp: September 30, 2010, 01:08:58 pm
content: If they used the GSM frequency with a Yagi Directional antenna like that would the meter burst into flames then?

author: Time
author_rank: Frequent Contributor
timestamp: September 30, 2010, 02:10:57 pm
content: It seems impossible that they hadn't already known about this. I almost feel like they swept the issue under the carpet upon discovery and it was only a matter of time before it resurfaced.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 30, 2010, 02:15:43 pm
content: Another possibility is that the problem started happenning afer a component change in production.Also bear in mind that they will have tested immunity at a specific power level (typically 3v/m), and it is quite possible that a nearby phone emits higher than that. Another factor is the GSM signal is 100% amplitude modulated, which may cause more havoc than a CW signal - I'm not sure if the normal EMC immunity tests specify any modulation.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: September 30, 2010, 02:50:22 pm
content: Quote from: Waifian on September 30, 2010, 01:08:58 pmI almost agree .. but only for the liquid crystal ...The pictured antenna looks to be for VHF - UHF bands .. 144 - 600 MHz

author: jahonen
author_rank: Super Contributor
timestamp: September 30, 2010, 03:33:56 pm
content: Looks as standard EMC test antenna. For radiated RF field testing, the test is made in 80-1000 MHz frequency range. RF signal has 80% AM-modulation, 1 kHz signal. Standard test levels are 3 V/m (domestic) and 10 V/m (industrial).Regards,Janne

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: September 30, 2010, 04:43:13 pm
content: I do not believe that the specific antenna , no matter how broadband it is , it can have an such range.Still any bit of information are welcome .As about the 3 V/m and 10 V/m , its an very unclear description .I am not rockets scientist , and I do repair RF transmitters with an average output of 2-10KW .Usually the antenna are 20 meters high from the ground level , and the systems are in small single room,made by bricks , or metal construction , at the top of the mountain .If any one likes to do real tests , this is the way to do it , get up on the mountain.

author: blackdog
author_rank: Frequent Contributor
timestamp: September 30, 2010, 08:54:21 pm
content: The antenna in the picture is a Log Periodic Type and has a verry high bandwith,se pdf in de link, on page 7.http://www.ets-lindgren.com/manuals/3147.pdfBram

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: September 30, 2010, 10:10:51 pm
content: From the above pdf (Antenna ) looks to be Maximum ContinuousInput Power:80 W at 1 GHz40 W at 5 GHzAny way , we all speculate here , lets go back , and become on topic.

author: EEVblog
author_rank: Unknown
timestamp: October 01, 2010, 12:04:48 am
content: Quote from: Kiriakos-GR on September 30, 2010, 10:45:34 amSomeone posted it in the comments section on the blog.Dave.

author: EEVblog
author_rank: Unknown
timestamp: October 01, 2010, 12:07:29 am
content: Quote from: mikeselectricstuff on September 30, 2010, 02:15:43 pmThe mobile phone also has modulation down at 218Hz, which is one of the reasons microphones pick it up so readily.See my GSM mobile phone blog.Dave.

author: EEVblog
author_rank: Unknown
timestamp: October 01, 2010, 12:11:06 am
content: Quote from: jahonen on September 30, 2010, 03:33:56 pmThis is a classic example of where even the strictest of EMC testing cannot possibly pick up or initiate every permutation of failure modes.Dave.

author: Neilm
author_rank: Super Contributor
timestamp: October 01, 2010, 03:35:23 pm
content: Depening on the test standard used, these frequencies might actually not be tested, or be tested at a much reduced power. EN61326 which is the EMC for Electrical equipment for measurement, control and laboratory use has several frequencies notched out. Also, testing over 1GHz is done at 1V/m much less than a mobile phone.Neil

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 01, 2010, 08:26:23 pm
content: Well my brain had stuck to this V/m calculation ...Did some Google search , every ones say its a complex formula ...But found an example that if it true , no one should ever power on an multimeter in a car running at the highway !!Quotehttp://copradar.com/preview/chapt8/ch8d2.html

author: jahonen
author_rank: Super Contributor
timestamp: October 02, 2010, 08:28:48 pm
content: The relation between electric field strength and power is (assuming isotropic ideal antenna at far field):I=E2/Z0, where I is the intensity [W/m^2], E is electrical field strength [V/m] and Z0 is the impedance of vacuum (approx. 337 ohms). For isotropic antenna, intensity I is P/(4*?*r^2) (i.e. the power fed to the antenna divided by the area of the sphere). So we can write P/(4*?*r2)=E2/Z0, or P=E2*4*?*r2/Z0 to get the power required (for isotropic case). So 3 V/m means say at 10 meters distance 33.5 watts to ideal isotropic antenna. If the antenna has directivity (i.e. non-isotropic case), then this directivity and radiation pattern should be accounted for. Of course it gets tricky if distance from the antenna is very small (like in this case) due to near-field effects, thus this simple method is not usable, but it gives some perspective anyway.Regards,Janne

author: jahonen
author_rank: Super Contributor
timestamp: October 02, 2010, 08:30:57 pm
content: Quote from: EEVblog on October 01, 2010, 12:11:06 amThat is true for all testing in general. You can't prove by any finite amount of testing that something is completely flawless, you can just show that it fails in some particular test.Regards,Janne

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 02, 2010, 09:22:11 pm
content: Personally all that I care for further testing on the 28II , are the two quirks found on the 87-5 .1) More audible beeper .2) The switching between high resolution to normal mode and backwards , at 19,999 volts .with out the need to drop the voltage at about 16,5 volts , so to enter at the high resolution mode by it self..If it does that , I will be super happy .... all the rest are all ready tested by Dave ..