GSM(including 3G) phones transmit at 1 or 2 watts, depending on the cellular system. You were getting lesser effects in a good coverage area because the tower tells the phone to turn down the power when it's closer.
It may not have bricked it because you didn't have the probes plugged in. You were getting 10 times the response from your router when the probes were attached, so it's reasonable to think that the fluke might have died if it had the leads in with the cellphone.
Plus, perhaps if that person's leads were wound as they measured would cause the leads to be more of an antenna to pick up those signals....I am just learning but that was my thought....
My 87-V is a ver. 011, I believe. Built in March. It doesn't have this problem (tested with AT&T GSM 850/1900, whatever the SGH-S125G uses), so whatever the problem was, Fluke definitely fixed it. I love this thing!
The thing with GSM is that it's not wideband, it may frequency hop, but it's a narrow TDMA signal which needs to be broadcast at high power since it's not redundant. For the tower to capture the stream of packets from the phone, it has to scream it at the top of it's milliwatts. most 3G systems though, are wideband and have a fair amount of data redundancy, so they broadcast on a wider spectrum with less power needed to establish a link. [from what I've learned about it anyway, I could be wrong]
I once had an issue with one of my PCs: an active GSM phone less than 20-30cm from it would cause it to spontaneously reboot. Turned out the caps on the motherboard had blown. It's really interesting how poorly shielded, malfunctioning, or poorly designed electronics react to GSM's particularly nasty transmit patterns!
The thing is that the power of cell phone's transmitter varies greatly during call time. The peak goes to initial "connect" then bs is regulating it based on many factors (like distance from bs (higher distance - higher power), coverage quality (lower quality - higher power) and so on). So the power usually is somewhat from 0.002 watts to up to 2 watts (everything is about 2G, 3G is 0.25w somewhat constant, LTE - 0.2w ). That multimeter can easily go bricky if you accidentally (or not) put you cell phone over it and someone calls you by chance, I think.
It's amazing that the dominant worldwide mobile phone standard causes horrendous interference to all manner of audio/video/digital gear. How did this ever get to market? Thanks for another great video!
The closer you are to the radio tower the less power the phone will transmit. Radio towers are responsible encryption on/off and device transmit power.
Mine didn't get bricked either but I'll be careful not too set it close to the cell again... By the way love the video's thumbnail with your aluminum hat. :)
Hey Dave. Do you ever remove the plastic film from your digital displays? It's intended to prevent the displays getting scratched during shipping. If not, do you think it might be a good idea if manufacturers permanently bonded it to the screen as an additional form of protection (on top of the other laminations already put there for the purpose). eh? eh?
It's probably the high power pulses GSM uses. One of the main drivers behind the design of UMTS is the reduced exposure to RF energy it produces. Since GSM is a TDMA system using a simple gaussian minimum shift keying radio, it produces a pulse train with significant amounts of energy at low frequencies- which is why they interfere with the microphone in your camcorder...
Looks like the Fluke 87V has something in the circuirtry resonant around your local GSM frequency and when you get a mobile phone near it you overload the circuits with a high voltage from the RF.
I hope the people at Fluke saw this. While it didn't damage your meter making this, I could see with people's phones and tablets being everywhere, meters being damaged over time by excess exposure. Hopefully the people at Fluke can improve their product.
Interesting! I got an 87V to get rid of the problems I was having with my Extech meter. I couldn't even take measurements with lights on in the shop. Using a flashlight it was ok. lol
understandable is the length of some wire inside is on quater wavelength or half wavelength then that will act as antenna and we would expect that. same goes for the PCB design is the curcuit printed on the PCB is of by coincidence of is exact or nearby length that will cause it to have massive interference. My guess is that the person who bricked have a phone with higher transmittion power although they should be standard but it might be little different.
I'm more than a bit disappointed you didn't figure out which bands your phone was operating on, then replicate those frequencies, as well as other frequencies used by GSM and CDMA to pinpoint the vulnerability. It would have been great to see you do it, because I would love to do it myself, but I just don't have the equipment to do such a test.
Great reviews and channels. I wanted to ask if you could do a video about multimeter probes. I haven't used insulation piercing test probes but they would make my life a lot easier if they are safe to use on 110 vac circuits. Proper use and your personal ratings would be very helpful. Maybe even another popular channel. Thanks for all your work.
Behaviour Modification, cough cough I am sure dave will love that. I love how there is a level of tech, and knowledge to why it exists, that even techs like dave here does not know about.
All mobile phones antennas should be internally shielded and tamperproof to stop them from harming sensitive test equipment. The world would be a better place if this was so ;)
GSM and 3G are two separate entities? Is GSM the encryption? Thanks for the video, Dave, as I will now purchase a Fluke 28-2 instead of the Fluke 87V. So, Fluke never responded to this video?
Note that even if your phone doesn't scramble your meter, it'll probably mess up your readings. My advice is to keep mobile phones & any other kind of RF source the hell away from your bench, just on general principles.Save that kind of interference for the reliability testing phase of your design!
Jasper Janssen Yep. Dave's a local guy. I remember when he first started posting YT videos & linking them to the Usenet electronics design group we both posted to.
Regarding bricking the Fluke, maybe you should try keeping it close to the meter while making or receiving a call. IIRC, GSMs peak at about 2-3 watts for a fraction of a second in these scenarios. Maybe that little "boost" is enough affect the firmware somehow.
I would guess it is the GSM power switching on and off that you hear in your video that does the interference, that also explains why your other RF sources do nothing (although the GSM is stronger).
No one's gonna believe me when I say this, but when I put my phone in GSM it wakes me up 3 or 4 seconds before a call or a sms. And it's not by hearing interference on some speakers or something like that, it's definetely something very sensitive on my body, probably the heart or the brain, I would guess. Any crazy explanations?
Maybe because You sense electromagnetic field around Your phone antenna and You sense it by your leg. Your brain recognize that electric signal as stimulus remebered as an experience with Your phone
@DanFrederiksen Yes, it's mine. Yes, I know all about the FSM. Yes, I'm a proud atheist. But I still have no idea what you were getting at with the robot burning etc?!
3G power is more spread among frequency using code division and spreading. Also every cell phone (UE in technical terms) is instructed to transmit at certain power, not less and not more, because more power brings more interference with other UEs 2G is simpler, it uses as far as I know time division, the power is more focused in frequency, more power, better quality
I have a question. Having trouble with my invisible fence pet containment system. Does anyone know how many volts the collar is supposed to emit when delivering a correction? I don't want to damage my meter to the spikes to test for functionality. Can't find that detail on the internet.
It's not static, it's "GSM buzz". Random traces and attached audio ICs can actually detect the GSM frequency (800-900 MHz) and turn it's audio-range AM-esque content (0-22 kHz) into that damn noise.
you238 close, base gsm is TDMA with a ~4 milisecond frame repetition so you get a 216hz fundamental, there are also 1/4 and 1/2 second (51 and 102 frame) repeats of control signals, giving the charistic pulsing. FDMA or CDMA won't have the same repetive cycles, so won't create a buzzing
Have you tried to shield the phone from the signal from the next gsm base station? With full reception the phone usually reduces transmit power - so "full bars" means less output power. Also: Try it with a HAM Radio station. I can knock up many devices even witth my handheld radio doing 5 Watts on 2 meters :)
I have this same problem with HP power supply from HP mini netbook. While i have incoming call and phone is near to PSU, my netbook shut down immediatly. I meed to plug off from AC power source, wait a second and connect it again then it work correctly
Replying years late just because I can... Pain is just an adaptation to reduce cellular damage. If a robot has a subroutine which causes it to retract its arm from fire or other sources of damage, I think it would be accurate to call that routine 'pain'. Sure, it's simpler than the animal version, but its purpose is the same. All pain does is motivate the brain to find a solution to the damage in a way which is very hard to ignore. Pain would be useless if it were easy to ignore.
Hmmmm, there's certainly something wrong there, I actually have heard stories about GSM phones killing nice expensive laptop computers, this is potentially very problematic as many people now use those little 3G USB modem sticks with laptops a lot. GSM really can cause heaps of interference problems, even DECT cordless phones cause problems, your DECT cordless phone caused your camera to produce a soft 50Hz hum, that happens here as well.
Hi. Your camera is giving you a hint. What causes the problem is not GSM carrier frequency itself (900MHz or 1800MHz) but TDMA modulation/coding that audio circuit in your camera could also pick up. It is 1/8th of the 4.615ms TDMA frame that translates to 217Hz that you can hear in your audio. Try any audio tool that can generate tones and generate 217Hz 12% pulse wave.
Doesn't a phone use more power to transmit when the signal is weaker? Seems like batteries go dead faster in areas with bad signals... maybe this is a factor?
I have problem with my 87v, the DC current reading has offset about 0.2 mA, it's a problem since I'm measuring 4-20 mA for field Instrument, does anyone know how to trim it to zero?
GSM(including 3G) phones transmit at 1 or 2 watts, depending on the cellular system. You were getting lesser effects in a good coverage area because the tower tells the phone to turn down the power when it's closer.
Also the probes were not attached
been using my 87V for over 15yrs, love it.
It may not have bricked it because you didn't have the probes plugged in. You were getting 10 times the response from your router when the probes were attached, so it's reasonable to think that the fluke might have died if it had the leads in with the cellphone.
Plus, perhaps if that person's leads were wound as they measured would cause the leads to be more of an antenna to pick up those signals....I am just learning but that was my thought....
I was thinking the same thing!
My 87-V is a ver. 011, I believe. Built in March. It doesn't have this problem (tested with AT&T GSM 850/1900, whatever the SGH-S125G uses), so whatever the problem was, Fluke definitely fixed it. I love this thing!
It's screwing up your camera's audio too.
Love the persistence. Thanks Dave
Thanks. I use an 87V in the field. Good to keep in mind if I get a call while working.
No effects on newer Fluke 87v ;)
The thing with GSM is that it's not wideband, it may frequency hop, but it's a narrow TDMA signal which needs to be broadcast at high power since it's not redundant. For the tower to capture the stream of packets from the phone, it has to scream it at the top of it's milliwatts.
most 3G systems though, are wideband and have a fair amount of data redundancy, so they broadcast on a wider spectrum with less power needed to establish a link.
[from what I've learned about it anyway, I could be wrong]
So much energy in your clips :)
@Films4You That's classic GSM interference in the microphone input. I have done a whole blog on this.
No one bothers with analog meters any more.
I once had an issue with one of my PCs: an active GSM phone less than 20-30cm from it would cause it to spontaneously reboot. Turned out the caps on the motherboard had blown. It's really interesting how poorly shielded, malfunctioning, or poorly designed electronics react to GSM's particularly nasty transmit patterns!
The thing is that the power of cell phone's transmitter varies greatly during call time. The peak goes to initial "connect" then bs is regulating it based on many factors (like distance from bs (higher distance - higher power), coverage quality (lower quality - higher power) and so on). So the power usually is somewhat from 0.002 watts to up to 2 watts (everything is about 2G, 3G is 0.25w somewhat constant, LTE - 0.2w ). That multimeter can easily go bricky if you accidentally (or not) put you cell phone over it and someone calls you by chance, I think.
What was Fluke's response to this?
It's amazing that the dominant worldwide mobile phone standard causes horrendous interference to all manner of audio/video/digital gear. How did this ever get to market?
Thanks for another great video!
The closer you are to the radio tower the less power the phone will transmit. Radio towers are responsible encryption on/off and device transmit power.
@333xan45 GSM can modulation sensitive microphone signals. Very common.
Mine didn't get bricked either but I'll be careful not too set it close to the cell again... By the way love the video's thumbnail with your aluminum hat. :)
3G transmission is typically over 900MHz in city areas... GSM is up in the GHz range.
I'm full of 1900 CDMA, and not one issue with my 87-V (built in March, so it's new).
sounds like its a pretty nice feature of the Fluke 87V, really expensive remote shutdown!
Is this problem rectified by the Fluke on this model? Can you check one that was manufactured in 2016?
Did you test the 87V with the GSM with the probes inserted?
Hey Dave. Do you ever remove the plastic film from your digital displays? It's intended to prevent the displays getting scratched during shipping. If not, do you think it might be a good idea if manufacturers permanently bonded it to the screen as an additional form of protection (on top of the other laminations already put there for the purpose). eh? eh?
+tasmedic This sparked an interesting thought. It seems to be more sensible that the film is replaceable.
Good idea. Maybe we could sell protective films for our displays. Oh, wait, they're already doing this for phones.....Hmm...
That might be a good idea. I mean, it had me wondering where I could purchase protective films, so.... :-)
Are the films for phones "non-capacitive"? Static and capacitance are a part of plastics and films...and the manufacturer should have values.
I left the plastic film on my stereo display for a year and when it turned dark yellow I tried to take it off and it would not come off.
came here from the Keysight video :)
It's probably the high power pulses GSM uses. One of the main drivers behind the design of UMTS is the reduced exposure to RF energy it produces. Since GSM is a TDMA system using a simple gaussian minimum shift keying radio, it produces a pulse train with significant amounts of energy at low frequencies- which is why they interfere with the microphone in your camcorder...
Obviously modulation signal of GSM frequencies couples with fluke 87's microcontroller, screen or power circuitry. Very interesting effect thank you.
Would be cool if you opened it to see what could the flaw on the 87V be.
You should try it with 100W UHF transceiver, that's gonna brick it :)
:D
U
Well thats gonna brick you sooner or later :D
Wow these RF signals affect the multimeter too. Hope the manufacturer fixed it too.
Looks like the Fluke 87V has something in the circuirtry resonant around your local GSM frequency and when you get a mobile phone near it you overload the circuits with a high voltage from the RF.
I hope the people at Fluke saw this. While it didn't damage your meter making this, I could see with people's phones and tablets being everywhere, meters being damaged over time by excess exposure. Hopefully the people at Fluke can improve their product.
dave do you have an original fluke 87 to test this. just wondering if my meter will have the same problem?
damn, I just bought 87V yesterday.
That's actually surprising. I sold my fluke 87 because I needed one with a amp clamp built in. But I used my 87 for years with no problem whatsoever.
What is your opinion on the SPERRY DM-4100A
Interesting! I got an 87V to get rid of the problems I was having with my Extech meter. I couldn't even take measurements with lights on in the shop. Using a flashlight it was ok. lol
understandable is the length of some wire inside is on quater wavelength or half wavelength then that will act as antenna and we would expect that. same goes for the PCB design is the curcuit printed on the PCB is of by coincidence of is exact or nearby length that will cause it to have massive interference. My guess is that the person who bricked have a phone with higher transmittion power although they should be standard but it might be little different.
I'm more than a bit disappointed you didn't figure out which bands your phone was operating on, then replicate those frequencies, as well as other frequencies used by GSM and CDMA to pinpoint the vulnerability. It would have been great to see you do it, because I would love to do it myself, but I just don't have the equipment to do such a test.
Great reviews and channels. I wanted to ask if you could do a video about multimeter probes.
I haven't used insulation piercing test probes but they would make my life a lot easier if they are safe to use on 110 vac circuits.
Proper use and your personal ratings would be very helpful. Maybe even another popular channel.
Thanks for all your work.
must've been a fluke :P
Thanks Dave
Flying Spaghetti Monster FTW !!!
So edgy
Confirmed in 2020 with a brand new fluke 87v with united states GSM that this is still happening.
Any word from Fluke about this? Have you sent them the video, Dave?
Just great, and I just purchased an 87V. Had I know I would have bought something else.
How is so far?Did you experience the same issue?
Behaviour Modification, cough cough
I am sure dave will love that. I love how there is a level of tech, and knowledge to why it exists, that even techs like dave here does not know about.
@DanFrederiksen I still have no idea what you are talking about!
All mobile phones antennas should be internally shielded and tamperproof to stop them from harming sensitive test equipment. The world would be a better place if this was so ;)
When you distant from mobile cell it tooks more signal power to connect than you standing just near it, that's why 3g in video didn't shut down fluke.
@EEVblog What should I search for on your channel to see that vlog?
I was wondering even though this is effecting the meter and maybe close to bricking it. Does it effect the calibration of any of the meters.
Did anyone notice how the transmission changes when Dave keeps quiet? Damn, Nokia has some good noise cancellation working in their phones...
GSM and 3G are two separate entities? Is GSM the encryption? Thanks for the video, Dave, as I will now purchase a Fluke 28-2 instead of the Fluke 87V. So, Fluke never responded to this video?
Note that even if your phone doesn't scramble your meter, it'll probably mess up your readings. My advice is to keep mobile phones & any other kind of RF source the hell away from your bench, just on general principles.Save that kind of interference for the reliability testing phase of your design!
Lionel Lauer I see you've been checking out old eevblog videos as well :)
Jasper Janssen Yep. Dave's a local guy. I remember when he first started posting YT videos & linking them to the Usenet electronics design group we both posted to.
Jeez, in 2008, I think?
I've seen the eevblog around occasionally from.. I think back when the newest was 100-odd, something like that, which is already quite a bit back.
You have the same mobile as me, i didn't think anyone else had an e71 as i seem to be the only one that bought one round my area.
light flickers...
99% demons
1% electrical problem lol
The mobile phone seems to have a good signal from the cell so will be running low power itself....
doesn't electronic material has to be tested on EMF before commercialisation?
You should have low signal as possible so it will transmit max power.
Regarding bricking the Fluke, maybe you should try keeping it close to the meter while making or receiving a call. IIRC, GSMs peak at about 2-3 watts for a fraction of a second in these scenarios. Maybe that little "boost" is enough affect the firmware somehow.
I would guess it is the GSM power switching on and off that you hear in your video that does the interference, that also explains why your other RF sources do nothing (although the GSM is stronger).
No one's gonna believe me when I say this, but when I put my phone in GSM it wakes me up 3 or 4 seconds before a call or a sms. And it's not by hearing interference on some speakers or something like that, it's definetely something very sensitive on my body, probably the heart or the brain, I would guess. Any crazy explanations?
***** You are not alone. I rely on this "feature" of the human body to get up for work in the morning. I tend to turn off my alarm before it rings.
Hugo Santos Does kryptonite affects you?
Maybe because You sense electromagnetic field around Your phone antenna and You sense it by your leg. Your brain recognize that electric signal as stimulus remebered as an experience with Your phone
Why probes on the wireless test, but not on the cell test?
Good stuff!
And what about the argument/fact that pain and pleasure are the same sensation, but perceived differently?
Will this happen only in fluke 87 v or in the oldest series too?
You should make this episode again with 5G and fluke
can you make a emf and try to bust the meter?
( just to check the breaking point on the fluke...)
3:50 even the camera is picking it up
@DanFrederiksen Yes, it's mine. Yes, I know all about the FSM. Yes, I'm a proud atheist. But I still have no idea what you were getting at with the robot burning etc?!
That's pretty wild ! Eric from Mn
Uh oh. Kryptonite! Am so tempted to test how my 87V will hold up.
3G power is more spread among frequency using code division and spreading.
Also every cell phone (UE in technical terms) is instructed to transmit at certain power, not less and not more, because more power brings more interference with other UEs
2G is simpler, it uses as far as I know time division, the power is more focused in frequency, more power, better quality
I have a question. Having trouble with my invisible fence pet containment system. Does anyone know how many volts the collar is supposed to emit when delivering a correction? I don't want to damage my meter to the spikes to test for functionality. Can't find that detail on the internet.
Why is the mic picking up the static?
It's not static, it's "GSM buzz". Random traces and attached audio ICs can actually detect the GSM frequency (800-900 MHz) and turn it's audio-range AM-esque content (0-22 kHz) into that damn noise.
you238 close, base gsm is TDMA with a ~4 milisecond frame repetition so you get a 216hz fundamental, there are also 1/4 and 1/2 second (51 and 102 frame) repeats of control signals, giving the charistic pulsing. FDMA or CDMA won't have the same repetive cycles, so won't create a buzzing
Have you tried to shield the phone from the signal from the next gsm base station? With full reception the phone usually reduces transmit power - so "full bars" means less output power.
Also: Try it with a HAM Radio station. I can knock up many devices even witth my handheld radio doing 5 Watts on 2 meters :)
@EEVblog Thanks. It was very interesting.
I have this same problem with HP power supply from HP mini netbook. While i have incoming call and phone is near to PSU, my netbook shut down immediatly. I meed to plug off from AC power source, wait a second and connect it again then it work correctly
Replying years late just because I can... Pain is just an adaptation to reduce cellular damage. If a robot has a subroutine which causes it to retract its arm from fire or other sources of damage, I think it would be accurate to call that routine 'pain'. Sure, it's simpler than the animal version, but its purpose is the same.
All pain does is motivate the brain to find a solution to the damage in a way which is very hard to ignore. Pain would be useless if it were easy to ignore.
I once had a high speed OP amp oscillating in a circuit and all the meters on the bench went haywire.
Is that your Thales lab coat??
@maxsnts May you be touched by his noodly appendage!
Hmmmm, there's certainly something wrong there, I actually have heard stories about GSM phones killing nice expensive laptop computers, this is potentially very problematic as many people now use those little 3G USB modem sticks with laptops a lot. GSM really can cause heaps of interference problems, even DECT cordless phones cause problems, your DECT cordless phone caused your camera to produce a soft 50Hz hum, that happens here as well.
you use a docsis 2 modem?
Hi. Your camera is giving you a hint. What causes the problem is not GSM carrier frequency itself (900MHz or 1800MHz) but TDMA modulation/coding that audio circuit in your camera could also pick up. It is 1/8th of the 4.615ms TDMA frame that translates to 217Hz that you can hear in your audio. Try any audio tool that can generate tones and generate 217Hz 12% pulse wave.
Good to know.
Your steering wheel is on the wrong side.
not if you're in Australia
No, YOU are on the wrong side of the earth.
I have the same phone :)
my fluke 179 doesn't react like your fluke when I put my phone next to it.
Wireless routers output anywhere between 20mw and 100mw Dave :)
Doesn't a phone use more power to transmit when the signal is weaker? Seems like batteries go dead faster in areas with bad signals... maybe this is a factor?
dave i'm almost sure it's some kind of inductorinside the fluke that makes this problem.
Where did Hal go?Y got him locked up,still???
God that sound is annoying, but at an octave down, it makes a nice bassline ;)
@kcj1993 Search for GSM mobile phone audio design
In the distant future anthropologists will date videos by looking at the cell phones used.
what if your are working on a GSM tower ?
I have problem with my 87v, the DC current reading has offset about 0.2 mA, it's a problem since I'm measuring 4-20 mA for field Instrument, does anyone know how to trim it to zero?
This means the GSM phone is over 3 V and will cause cancer!
how does it do that.
and some people called your a fluke fan boy :-) Well, that meter did had a hart time.