Author Topic: Fluke 87V screen goes crazy with WIFI & Cell phone signals  (Read 42480 times)

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Offline Twistx77Topic starter

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Fluke 87V screen goes crazy with WIFI & Cell phone signals
« on: September 12, 2010, 11:14:32 pm »
Hi,

Today I was measuring some stuff with my 87 and suddenly the screen went crazy (turned on and off quiclky) I thought there was something wrong with the MM but then I moved and it went back to a normal state. I figured it was my router which was like 20 centimeters away from the MM.

Then I tried to get it close to my cell phone and make a call and it could pick up the signal from 40 cm away.

I thought that at least the WIFI signal wasn't strong enough to interfere with the MM. How reliable can this MM be close to a 2kW motor for example?

 
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #1 on: September 13, 2010, 12:45:21 am »
The only MM type that RF has an very minor effect on it , its the analog ones .
 

Offline Mambo

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #2 on: September 13, 2010, 01:40:58 am »
How reliable can this MM be close to a 2kW motor for example?

Very....you should be using the low pass filter mode. Decent meters have a wide AC input typically 100kHz (still well below what I'd expect your router to be outputing) which allows noise to appear. Cheap meters due to limitations normally only show AC voltage upto 500Hz and this is where problems can arise.  Many meter's have issues with motors and noise, normally from Pulse Width Modulated Drives (also known as Varaible Speed Drives). I can't talk for noise from Routers, but good practice is to use the low pass filter in any area that has other sources floating around. Lesser meters don't have that function, but to be honest they often don't need it because they can't see the higher frequency voltages anyway. This is not a fault of the 87-V, it actually highlights how good they are...but it can have it's downside.

Is it possible that you have a noisy switchmode power supply within thr router or other causing the noise, as the RF output of the router is not the likely cause imo.

 
« Last Edit: September 13, 2010, 01:45:13 am by Mambo »
 

Offline JohnS_AZ

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #3 on: September 13, 2010, 02:39:41 am »
Wow, a whole new course of tests for Dave to do with all of his multimeters. :-)
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Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #4 on: September 13, 2010, 08:49:52 am »
Wow, a whole new course of tests for Dave to do with all of his multimeters. :-)

About what ?   Testing RF interference ..

If so , i would make the challenge larger ,
and I would suggest the DMM to be tested next to TV and Radio  ( UHF - FM  band ) transmitters  with RF output  of 2 - 20 KW  ..      ;D
« Last Edit: September 13, 2010, 08:52:20 am by Kiriakos-GR »
 

Offline Twistx77Topic starter

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #5 on: September 13, 2010, 03:58:26 pm »


Very....you should be using the low pass filter mode. Decent meters have a wide AC input typically 100kHz (still well below what I'd expect your router to be outputing) which allows noise to appear. Cheap meters due to limitations normally only show AC voltage upto 500Hz and this is where problems can arise.  Many meter's have issues with motors and noise, normally from Pulse Width Modulated Drives (also known as Varaible Speed Drives). I can't talk for noise from Routers, but good practice is to use the low pass filter in any area that has other sources floating around. Lesser meters don't have that function, but to be honest they often don't need it because they can't see the higher frequency voltages anyway. This is not a fault of the 87-V, it actually highlights how good they are...but it can have it's downside.

Is it possible that you have a noisy switchmode power supply within thr router or other causing the noise, as the RF output of the router is not the likely cause imo.

 

I understand that it could pick up noise from a motor and give you a miss reading. That's when the low pass filter would be helpful the problem is that I don't get a miss reading but the screen just turns or and of or shows a "----" reading.

Also I've test the issue with my own cell phone since the first time was with anothers person cell phone and I think both times I saw the problem was only the cell phone and not the router and the cell phone since both were in the same table and I tried today with my own router and it doesn't happen anymore. Also I tried with my own cell phone and it doesn't happen " as much" as before, only when I have my cell phone like 5 cm away, if I take it farther it doesn't happen.


 

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #6 on: September 13, 2010, 04:52:34 pm »
so the Fluke87 is not so that undestructable huh? they should design a EMI proof DMM, the Fluke 88 or something and "double the price" of Fluke87! then we will get a super high end super reliable super everything DMM.
« Last Edit: September 13, 2010, 04:57:54 pm by shafri »
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Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #7 on: September 13, 2010, 08:45:10 pm »
so the Fluke87 is not so that undestructable huh?


Personally I do not accept as fact , an single report about an such issue ...
Specially with out an proof .. picture or video ..  

There is people who do the maintenance of very powerful re-transmitters (non cable TV systems ),
no one had report an issue so far .

Mobile phones operate at 1G and above ..

Every DMM have inner frequency clocks ,  an instant interference its not the end of the world . 
« Last Edit: September 13, 2010, 08:53:14 pm by Kiriakos-GR »
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #8 on: September 13, 2010, 08:55:24 pm »
Also I tried with my own cell phone and it doesn't happen " as much" as before, only when I have my cell phone like 5 cm away, if I take it farther it doesn't happen.


What brand and model is it ?? 
 

Offline Mambo

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #9 on: September 13, 2010, 09:06:01 pm »
I understand that it could pick up noise from a motor and give you a miss reading. That's when the low pass filter would be helpful the problem is that I don't get a miss reading but the screen just turns or and of or shows a "----" reading.
Also I've test the issue with my own cell phone since the first time was with anothers person cell phone and I think both times I saw the problem was only the cell phone and not the router and the cell phone since both were in the same table and I tried today with my own router and it doesn't happen anymore. Also I tried with my own cell phone and it doesn't happen " as much" as before, only when I have my cell phone like 5 cm away, if I take it farther it doesn't happen.

Twistx77, I ask again are you using the 87-5's low pass filter when this happens...
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #10 on: September 13, 2010, 09:08:00 pm »
What low pass filter had to do , with any interference at the DMM display ?   
 

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #11 on: September 13, 2010, 10:16:14 pm »
so the Fluke87 is not so that undestructable huh?
How was the DMM destructed?

they should design a EMI proof DMM, the Fluke 88 or something and "double the price" of Fluke87! then we will get a super high end super reliable super everything DMM.
Nah, they'll just offer you a free bumper ;).

I would expect some EMI immunity, though not perfect. Interference from 40cm with a cell phone sounds pretty bad, though.
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #12 on: September 13, 2010, 11:03:54 pm »
I believe him ... I just damaged my 87-5

The problem stands when the mobile phone transmits ,  the display it does flashing like crazy ..
Random  fixed  labels appear .

The left side its the most unshielded ...  

I got my mobile ( was on call )  close to the range switch , and the display stopped working ,
got blank ...

I switched the meter  off  and on , boots but with an error ..
I am suspecting  that the software of it , become corrupted ..  
I need to go to sleep , its late up here , I will let it with the battery removed all night ,
and see if it will recover ..

If not .. I will have to find out the true face of Fluke support , at a minimum damage of 40 EUR just shipping cost ..

More about it , tomorrow ..  
Pictures as always ..


« Last Edit: September 14, 2010, 05:25:17 pm by Kiriakos-GR »
 

Offline PetrosA

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #13 on: September 14, 2010, 02:43:44 am »
Can anyone narrow it down to GSM vs. 3G and what frequency?
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Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #14 on: September 14, 2010, 12:38:49 pm »
Can anyone narrow it down to GSM vs. 3G and what frequency?

There is no many heroes around, to do such tests ...

My phone was set in manual to operate at standard GSM , as the 3G network its not powerful in my location,
and the continuously search for 3G network , it was killing my battery run time.

Now, about me and the DMM, it looks that I got in deep shit .
I contacted two service centers in Greece   , contacted Holland and England .
The two Greek Fluke centers , asked me pictures and proofs of the problem so to inform Holland .

Holland forward my email in to a third " Dealer " who contacted me saying that ...
I have to send the DMM to him ,  he will send the DMM to Holland ...
If Fluke in Holland  decides that its not an damage caused by the user ,
it will by repaired for free .. and shipped back for free too ..

If not , the shipping cost and just the inspection it will had an cost of 150 EUR ..

I am calm , but I will hunt down Fluke even in Court , if they do not act in good faith ..

Its a fact .... your GSM mobile it can trash your FLUKE 87-5  !!

This is an ridicules cause of damage , totally undocumented and a good reason for fight ..

Today at work , we got an small  Mastech DMM ( of value 15$ ) and we set four GSM phones ( calling  its  other = all active transmitting )   next to it , and it survived and works great.    

I am going to send it , and hope for the best .
I do not like even to think what it will happen if they did not recognize this issue as their fault,
as I said, I will start my personal war against them ..  
« Last Edit: September 14, 2010, 05:28:34 pm by Kiriakos-GR »
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #15 on: September 14, 2010, 12:49:20 pm »
wondering and made a test on my Uni-T. i think its EMI passed, with or without the probes connected. this is a big issue IMO. some of our fellas here have caught Fluke "pantless" or "pantyless" :D


The attachment looks damaged , I can not download the file ..

Yes, thats an ultra major flaw  for the specific model , the Fluke 87-5 ..
And some one , needs to give allot of explanations about it ..  
« Last Edit: September 14, 2010, 12:52:54 pm by Kiriakos-GR »
 

Offline Mambo

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #16 on: September 14, 2010, 02:45:12 pm »
 Mastech DMM FTW....wow who would have thought it. I'm glad I never tested my 87-V, as claiming warranty might be a problem.
 

Offline saturation

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #17 on: September 14, 2010, 03:19:02 pm »
Revealing thread, if 'Err' appears on the 87V, it can mean the EEPROM has been corrupted!

K, given you are most affected, have you tried the system status check procedures?  Download the 87V service manual and try the test procedures beginning on page 14, you have nothing to lose.

Report back whatever you find please.

To start, press & HOLD down AUTOHOLD button, then turn the rotary switch to any position from OFF.  The LCD will show all functions on, you rotate from function to function, I forget the sequence, but it should show, light up all LCD annunciators, firmware version number, meter number, etc.,then you can proceed with the other tests.

You can also RESET the 87V, just go through the password reset procedure in the manual.




Best Wishes,

 Saturation
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #18 on: September 14, 2010, 03:45:27 pm »
The attachment looks damaged , I can not download the file ..
database error sh*t was happening and the attachment might got scrambled! here again.

Hey tester  :)  the mobile should be on calling mode , not stand-by .

Edit I can not see clearly the screen , does it call some one ?
« Last Edit: September 14, 2010, 03:50:49 pm by Kiriakos-GR »
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #19 on: September 14, 2010, 03:48:35 pm »
Hi saturation  , I will try the tests ... I have nothing to lose .

About the reset , it is only documented as Password reset ... nothing more ..
Any way I will do my homework , and I will post soon my findings .

Thanks for the help, I do appreciate it .
 

Offline jahonen

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #20 on: September 14, 2010, 03:56:42 pm »
I'm quite amazed that mobile phone really did permanent change to the DMM. I have seen many times that things go berserk in EMC RF-immunity testing (conducted or radiated) but there has been usually no permanent damage, just temporary malfunction. However, probably no real hardware damage but just some corrupted configuration memory (CPU went berserk and corrupted vital data).

Regards,
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Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #21 on: September 14, 2010, 04:33:14 pm »
Ok , I did my best about testing , my fast reply will be , that I have lost the firmware ...

The indication F8- translates to  Boot-rom F8X = active .
Normally the DMM posts like F87 and power on ..

The Missing  F87 looks to be the specific firmware , that the specific DMM uses .
And I say " The specific  DMM "  , simply because  the same Boot-Rom IC   it can be used in many Fluke models ..  exactly the same chip as hardware ..

Now , the boot-Rom by it self , holds active some part of software used for diagnostics , like display light - battery status - display status .... all those are working .

The next step for the multimeter after the ROM test , are to load the specific firmware for the Fluke 87-5 .
My firmware got corrupted , there is possibly an file size change to it ,  and the Boot-Rom identifies it and posts  ERROR .

I have awareness of what happens inside it ,  but it looks that there is nothing for me to do about it.

On a second note , the DMM has on the Boot-Rom, storage'd data , like last calibration log and such,
if those got messed up , Fluke will have knowledge about it , and it will cancel the warranty.

I got informed that if everything goes well , Fluke will provide to me another 6 months warranty on a signed paper .


On a third note , I would love to had the choice to reset it , if there is an such progress ,
if some one has an solution , and does not like to write it in public , just use an Private Message ..
 


 
« Last Edit: September 19, 2010, 11:53:37 am by Kiriakos-GR »
 

Offline PetrosA

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #22 on: September 15, 2010, 02:54:23 am »
I offer my sympathies to you guys! This really sucks and now that Kiriakos has a bricked 87V it's hard not to believe it.

I would hope that Fluke addresses the issue. I can certainly imagine situations where you have your meter on at work, get a phone call, put it on speaker and hold the phone near the meter, or lay the meter and your phone on a counter or bench and talk to someone while taking readings. If a simple GSM signal from a phone can brick a really expensive meter, someone didn't do their testing thoroughly enough. If it's not specific to GSM, would a walkie talkie do the same thing (strong signal burst)?

P.S. some sick, self-destructive part of me wants to test my Agilent, but the more developed part of my brain is holding me back ;)
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Offline EEVblog

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #23 on: September 15, 2010, 03:16:32 am »
Damn, that's serious!
I would have expected the 87V to be fairly immune to EMC, but I'm not entirely surprised a high power RF source can upset it.
But to permanently brick it?, that's really unacceptable.

I'm led to believe the 87V Ex model has added EMC shielding, but I can't find details on that.

So we have one case of interference by WiFi, and another of bricking by mobile phone. This doesn't sound like a 1-off.

Should I attempt to test the susceptibility of mine?  ;D

Dave.
 
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Offline MrPlacid

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #24 on: September 15, 2010, 04:07:49 am »
Should I attempt to test the susceptibility of mine?  ;D

Dave.

Man, it's like Toyota all over again.

Dave, test your DMM and remember to take video. I bet fluke will replace yours free of charge since you're well respected in the DMM community.


« Last Edit: September 15, 2010, 04:14:38 am by MrPlacid »
 

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #25 on: September 15, 2010, 04:50:04 am »
My Mastech MS8226T used to glitch if I connected it to a circuit with a rather high dV/dt (an unfiltered inverter, for instance) but it stopped doing that after I took it apart to clean the dial switch. I suspect there was a dirty connection that caused a control signal to drift near a threshold and made it particularly sensitive to noise. (I'm thinking about putting dielectric grease on the contacts next time I clean it, but I'm concerned if it could affect its accuracy.) It has not "broke" from this but I'm not surprised since the microcontroller is probably an OTP part. Not sure why you would need to upgrade firmware on a simple multimeter anyways.

I suspect yours was defective (bad shielding or filters) since there would otherwise be lots of broken meters from amateur radio experimenters.
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Offline Twistx77Topic starter

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #26 on: September 15, 2010, 08:42:25 am »
Hi Folkes,

Sorry for my absence but I've been very busy since I'm going on a trip for a month.  I was going to send a video of it, but now that I've seen what happened to Kiriakos (Sorry about that) I don't think I'll keep trying.

The first time it happened to me, I don't know if the phone was in 3G or GSM mode since it wasn't mine. The second time was in GSM so I wouldn't dare to try with 3G ... Maybe Dave would?

Luckily I didn't get the error and it seems to be working just fine for now. I hope it stays that way.

By the way mine is the original Fluke version.
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #27 on: September 15, 2010, 09:13:26 pm »
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #28 on: September 15, 2010, 09:21:58 pm »
So we have one case of interference by WiFi, and another of bricking by mobile phone. This doesn't sound like a 1-off.

Dave.

I believe that and in the first case, the mobile phone was responsible.
The WiFi has an output of few mW .... the mobile phone has an output of 0.4 - 0.8 Watt ..

So the mobile phone looks stronger , but still  its ridicules as event.

Who will ever believe that if you throw an aspirin over a train , the train will get out of the rails !!    


I offer my sympathies to you guys! This really sucks and now that Kiriakos has a bricked 87V it's hard not to believe it.

I would hope that Fluke addresses the issue. I can certainly imagine situations where you have your meter on at work, get a phone call, put it on speaker and hold the phone near the meter, or lay the meter and your phone on a counter or bench and talk to someone while taking readings. If a simple GSM signal from a phone can brick a really expensive meter, someone didn't do their testing thoroughly enough. If it's not specific to GSM, would a walkie talkie do the same thing (strong signal burst)?

Totally agree ..

And the point are that even if I get from Fluke an positive up come , an working DMM , what I will had to do ??  babysitting it for life ?  

Just tested and the rest gang .... the killer mobile phone did not effect them ..



« Last Edit: September 15, 2010, 09:46:24 pm by Kiriakos-GR »
 

Offline PetrosA

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #29 on: September 16, 2010, 03:26:49 am »
If they fix it, just wrap it in aluminium foil to keep it safe from cell phones AND aliens. ;)
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Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #30 on: September 16, 2010, 03:25:45 pm »
a video review on this should be done. to warn everybody and to open Fluke's eyes (or hopefully pant :D)

Well this issue worth's an international recall of any Fluke 87-5 ( return to base ) , for adding in it " extra shields " and inspection .

And speaking about video review , I like to see how the similar Metrawatt DMM  stands against the same risk.
An active  mobile phone standing next to it , 1-2 centimeters next to it (at any direction of the case) and faceplate , will be very reviling .

 
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #31 on: September 16, 2010, 03:31:36 pm »
If they fix it, just wrap it in aluminium foil to keep it safe from cell phones AND aliens. ;)

Its not that simple PetrosA , any addition as shield , it could work as shielding , but its possible to compromise the behavior of the DMM ( safety against transients ) .

And so ....  Its not that simple..  
 

Offline jahonen

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #32 on: September 16, 2010, 06:23:29 pm »
And speaking about video review , I like to see how the similar Metrawatt DMM  stands against the same risk.
An active  mobile phone standing next to it , 1-2 centimeters next to it (at any direction of the case) and faceplate , will be very reviling .

Tried this on my new Metrahit Energy. While no permanent change was done, the nearfield RF clearly affected the measurement results, something that one would expect. Here is a record of measurement values while I exposed the meter to the GSM phone. I also increased the transmitter activity by rubbing the microphone so that it has to transmit the resulting noise. Readings returned quite fast to normal just as I moved the phone away from the meter. This was easy to do since I have the IR cable for the meter. Just turned the "send" function on.

Also, tried it on my Fluke 89 IV. It beeped once (couldn't repeat this even after several tries), but reading remained quite stable. Also no permanent change to the DMM. Unfortunately, no logged graph here, I don't have IR cable for this one.

Regards,
Janne
 

Offline jahonen

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #33 on: September 16, 2010, 06:48:04 pm »
And, isn't it strange coincidence that US FCC EMC testing does not require immunity testing, only emissions must be controlled and Fluke is US based company :P. However, manual states that RF fields up to 3 V/m should not even cause deviation from specified accuracy, but that is the test level for household equipment, industrial test level is 10 V/m, and automotive level is 30 V/m IIRC. I wonder if the result from 10 or 30 V/m immunity test would be completely different.

Regards,
Janne
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #34 on: September 16, 2010, 07:15:55 pm »
Thank you Janne for the test ...  you had enter at the club of the braves , like it or not  :D

I would care very less , if the interference was effecting temporarily the accuracy of an measurement.

I do not care either if the UNI-T pictured above , by the interference of the mobile phone ,
it starts the beeper to make sounds ....  audible sounds , like the computer speakers do , when an mobile phone are active next to them !!

I had say this an in another topic , those latest high-tech multimeter 's , are computers dressed up like common multimeter 's .
This scenario makes them susceptible to common factors that troubles any modern computing system.
EMI or RF power or even common static electricity can kill them at easy ...

Yes I agree that at the automotive Fluke multimeter,
there is at list some awareness about this possible " issue " and the specs looks better, at list on paper.

The only comment that I can make , are that I am not aware any cars electricians that are willing to spend that money , but this is another subject, just by it self .

So the Metrahit Energy  passed the test ,  got in the river and came out dry ,
that's what matters the most , at list to me.


  

  
« Last Edit: January 15, 2011, 02:22:35 pm by Kiriakos-GR »
 

Offline MrPlacid

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #35 on: September 17, 2010, 09:35:21 am »
If they fix it, just wrap it in aluminium foil to keep it safe from cell phones AND aliens. ;)

Me no hero. But I did put aluminum foil in the rubber case. The one on the left doesn't have the aluminum foil inside.
« Last Edit: September 17, 2010, 09:36:53 am by MrPlacid »
 

Offline MrPlacid

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #36 on: September 17, 2010, 06:15:19 pm »
Hmm, maybe there is something to this "mobile phones cook your brain" theory  ;)

I have always wondered about that since homemade bug transmitter don't have much juice to go very far.
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #37 on: September 17, 2010, 06:43:43 pm »
MrPlacid  I like the way that you think , like running ahead for the cure .....

Its something that I expect to happen near soon ,  like  an  " upgrade pack for 87-5 extra shields " by Fluke.
I have not mail my multimeter to Fluke yet .. (Busy week )

My only comments - advices about this experiments of yours..
First the mobile phone must be active - calling some one or ringing , so to effect the meter ...

Secondly in order this " shield of foil " to act as shield , it must be connected at minimum with inner bottom shield ...  (metal cage )  Right now works most as antenna !! and its best to remove it.

There are aluminum strips with glue at the one side , used by the electronic industry exactly for this purpose, as bridge of external shields.

There is also another smart way about shields ,  by painting the inner plastic of the device with chrome based paint ... and copper contacts touching it from the PCB , an solution found on ACER laptops.
But I think that safety regulations will forbidden an such solution to be used on DMM that have to do with Industrial use and High Voltage !!     
 

Offline MrPlacid

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #38 on: September 17, 2010, 07:25:15 pm »
Kiriakos-GR, I am no hero so I didn't want to test it with the phone calling  ;D However, what you said make sense such that I removed the aluminum and I doubt that I ever brick mine anyways.

I thought how fluke would rectified the situation such as painting the inside of the case.  But wouldn't in the long term, chip paint might cause an issue down the road?
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #39 on: September 17, 2010, 08:09:32 pm »
Kiriakos-GR, I am no hero so I didn't want to test it with the phone calling  ;D

In this case I prefer no posting with out reason ..  in this thread ..  
Why ? ... because Its possible to use this link , at the future,
if Fluke did not act wisely about supporting me.

Normally as human , after an such an damage at one so expensive hardware,
I should had loose all my hair by pooling them  , from my temper ..  

I choose to keep my voice down , and even the added video on the web , are with out tags and name,
because I count  on their cooperation .

I plan to respect them as company, at the same level that they will respect me , as an customer.

The specific " technical Issue " blows away any limitations about the warranty plan that Fluke apply by their own will , about world wide coverage .

If Fluke are unaware about this issue , my multimeter will get to Holland and from there back to USA for QC examination ...  and I will get an boxed one as resolution . (hopefully )

 
 
« Last Edit: September 17, 2010, 08:11:54 pm by Kiriakos-GR »
 

Offline EEVblog

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #40 on: September 18, 2010, 05:00:59 am »
I've tried it!, and can confirm it's real problem. I was not able to brick mine though.
All filmed and edited, blog #112 on it's way...

Dave.
 

Offline jahonen

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #41 on: September 18, 2010, 06:15:55 pm »
I've tried it!, and can confirm it's real problem. I was not able to brick mine though.
All filmed and edited, blog #112 on it's way...

Dave.

Too bad you did not feed the DMMs with something real to measure, like a resistor in ohms range or some voltage (battery for example) in DC volts range. It would have been interesting to see if the measurement accuracy of the other meters which were not completely screwed up is affected.

However, getting consistent results in tests like this is often difficult, but Fluke made it quite so, by shutting itself consistently :)

Regards,
Janne
 

Offline saturation

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #42 on: September 18, 2010, 06:39:31 pm »
Let Fluke know, I'd love to hear the official word from them, and they do listen to eevblog.

I've tried it!, and can confirm it's real problem. I was not able to brick mine though.
All filmed and edited, blog #112 on it's way...

Dave.
Best Wishes,

 Saturation
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #43 on: September 18, 2010, 07:08:12 pm »
I have pack my multimeter and its ready to be shipped on Monday 20 ..

Thank you Dave, that you did verify, by your test this issue.

I had took some high resolution pictures , of the DMM it self ,
some points of interest . 

Points of interest :
1)  some markings on the PCB  ( PCB details )
2) the totally unshielded area under the display , especially the left side.
3) Some dates of parts in it ... But I believe that Fluke does not needs any of that,
they read the Eprom ( chip data ) and they know all the details .
4) One screw half bolted on the low end of the shield , this screw does not move so to screw it all the way in or out ... an accident in the assembly line probably , and so I do not touch it further.   

I have wrote an letter to them , with not salty or either sweet voice tone.

Any way , I hope for the best, and I move on..

Pictures .. 


 
   

 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #44 on: September 18, 2010, 07:24:57 pm »
What vidz ?    Dave posted the video .... I am going to see that ..  :) 

Thanks shafri for your good words , lets hope that the people behind the company,
are more friendly that the warranty documents that they print .

 
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #45 on: September 18, 2010, 07:53:02 pm »
Nice video .... an true tonic for my current gray mood ..

I liked especially the advice ... Like let the Professionals to brick their DMM ..  ;D  
They can do it best !!  

Oh my ..  :D

I like to thanks Dave and the forum members, from the bottom of my hart ,
I had form the idea ,  that you can not found such of  support  in public forums  ..

Jee I need a Beer ...  :)  

 

Offline Simon

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #46 on: September 18, 2010, 09:05:53 pm »
Kiriakos-GR! you are now famous i think, your name is mentioned in the vidz! i think more gals will be into your mail :

oh so thats how it's done  8) lets see what can I inocently wreck,.... hm no the rigol it too precious,..... the am220 DMM is not precious enough....... the VC99 nobody will care about, oh well looks like I'll never be famous  :P

sorry to hear about you fluke Kiriakos (and yes there is a pun there - fluke) it's amazing a company like fluke let that slip, from what dave shows in his video the multimeter is "tuned" to the GSM frequency (of which by the way there are two ranges 850-950 and 1850-1950 MHz - wonder which one is doing the damage)
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #47 on: September 18, 2010, 10:05:57 pm »
I just checked some lists about the GSM frequency , Australia and Greece use both 900/1800 .

But I will put my bet on the 900 one ,
simply because you get more output from any transmitter, always at the lower frequency ..

The mobile phones has an single output circuit and antenna .
At the 1800 , they have lesser output , but cleaner band , so there comes the gain.

I was believe so far that at 3G ,  the GSM 900 works together with the 1800 , so to double the data bandwidth ,  on Daves video it looks that its not working that way ...
If it was , the GSM it should continue to cause trouble on the 87-5 .

Another explanation could be , that I do have right , but when the 3G gets active , there are both frequencies in use ,  but at an very lesser output.   
 

Offline Wartex

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #48 on: September 19, 2010, 01:14:11 am »
Fluke 289, Amprobe 38XR, Extech EX530

 

Offline Simon

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #49 on: September 19, 2010, 07:12:24 am »
I just checked some lists about the GSM frequency , Australia and Greece use both 900/1800 .

But I will put my bet on the 900 one ,
simply because you get more output from any transmitter, always at the lower frequency ..

The mobile phones has an single output circuit and antenna .
At the 1800 , they have lesser output , but cleaner band , so there comes the gain.

I was believe so far that at 3G ,  the GSM 900 works together with the 1800 , so to double the data bandwidth ,  on Daves video it looks that its not working that way ...
If it was , the GSM it should continue to cause trouble on the 87-5 .

Another explanation could be , that I do have right , but when the 3G gets active , there are both frequencies in use ,  but at an very lesser output.   


No 3g is a band of it's own I believe it is around 2700 MHz but don't quote me on that
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #50 on: September 19, 2010, 09:16:08 am »
Simon You are almost correct , about the 3G frequency .

Under this page of specs about my phone , http://www.gsmarena.com/sony_ericsson_k600-1043.php  .
( This phone had an street price of 400 EUR as Free device , I payed 180EUR as new subscriber at the Vodafone network , and now I am currently at the Wind provider )   

Its listed as  
2G Network     GSM 900 / 1800 / 1900
3G Network     UMTS 2100  

This page shows the The supported frequency bands in Greece
http://www.gsmarena.com/network-bands.php3?sCountry=GREECE

This page shows the The supported frequency bands in Australia
http://www.gsmarena.com/network-bands.php3?sCountry=AUSTRALIA

« Last Edit: September 19, 2010, 09:20:20 am by Kiriakos-GR »
 
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Offline Pinky

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #51 on: September 19, 2010, 02:45:37 pm »
Fluke 289, Amprobe 38XR, Extech EX530


Is there any special reason why you performed the tests on all DMMs switched to DC mV range and not to AC mV range as it should be done?  ???
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #52 on: September 19, 2010, 03:16:07 pm »
There is no specific range Issue ,  its the inner CPU of the multimeter that gets effected..   
 

Offline Simon

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #53 on: September 19, 2010, 03:17:28 pm »
Simon You are almost correct , about the 3G frequency .


( This phone had an street price of 400 EUR as Free device , I payed 180EUR as new subscriber at the Vodafone network , and now I am currently at the Wind provider )   

Its listed as  
2G Network     GSM 900 / 1800 / 1900
3G Network     UMTS 2100  




your using Wind ? good luck, we used them in Italy and they were crap. at one time we got a letter telling us we might loose the service because their roaming contract with TIM (Italy's version of mobile BT) was going to run out and they had not renewed it. luckily they were able to renew it.
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #54 on: September 19, 2010, 04:54:19 pm »

your using Wind ? good luck, we used them in Italy and they were crap.
Same story here , they have poor signal coverage in my area , that drains my battery faster than when I was in vodafone.
Currently I am originaly on an network called as Q-card  that was with vodafone, and now it merged with Wind ..  yea " Good luck "   :)
 
 

Offline Kiriakos-GR

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Re: Fluke 87V screen goes crazy with WIFI & Cell phone signals
« Reply #55 on: September 21, 2010, 11:04:48 am »
At this point I like to connect the threads .. 

Adding too the Video response of Dave ..   



And the link of the last thread related to it ...

https://www.eevblog.com/forum/index.php?topic=1307.0

If you need to post something follow the above link. 
 
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