I wish TH-cam recommendation algorithms would take the educational quality into account to promote channels like this one. Anyways, I'm so glad I found this channel!
Thank you for keeping the presentation simple and easy to make the subject understandable....best videos and presentation i have seen in the EMC world...Thank you
around 5:00, The PCB material forms a dielectric that makes it a capacitor. That is why the insertion loss gets lower. Better test it with only a copper plate. I sometimes make capacitors for RF filters from double sided PCB. But a very nice serie of experiments. Well done
You and your channel are great! And this video is another outstandingly good video-class for these concepts you presented - magnetic (previous) and electric (this) field shielding. I’m curious how certain vídeos as these ones were made, the setup and their making-off. I believe we all would appreciate very much if you could prepare some “making-off” videos, showing the preparation of the demonstrations, the selection of instruments, how they were adjusted/aligned, etc. Thank you for demystifying, simplifying and elucidating for us several topics.
It would be great if you can comment on how to provide EMI/EMC shielding for INS module where roll pitch and yaw are measured. And only yaw value gets disturbed a lot when testing is carried on a Rate Table.
Great demonstration! A question: Will the transferred field be affected if you add the grounded plane close to the source plane, but outside not between the planes, as demonstrated? Could you test this? I was speculating that crosstalk and EMF could be improved in a PCB just by adding grounded copper tape to the surface with a thin varnish between the tape and the pcb.
Great video 👍🏻 Maybe it's worth mentioning that the return path of the ground also highly effects the attenuation of the signal. Ideally you want to make that as short and direct as possible to the source (the sending plate in this case) Especially in the MHz region.
You are right - the shield connection to GND, as well as the GND to noise source; or signal reference connection is important. I guess this can turn into a much more detailed discussion when the ground its self is not very uniform...
Another fascinating, although simple, experiment. The results were not a surprise, but I have never seen the results with my own eyes (or taken the time to do it!) So, thanks Fesz. I do suspect that the thin metal shields (at 3:03) will not attenuate H fields too well, but I wonder if you would be interested to investigate that claim?
Well, I did look at magnetic shielding a couple weeks ago and one of the tested materials was a tin plated copper PCB. The size of the "shield" was much larger than what I was using in the Efield experiments mainly because of the size of the coils needed to generate and measure the magnetic fields, but effectiveness should not be related to size, I mean, the shield should cover the noise source (or the sensitive circuit) but as long as this is achieved if the shield is bigger will not make it work better. I'm not sure if that was what you are expecting.
I am looking to hide a box of gold from a metal detector, how might I do this? From your video it seems like I might be able to somehow create a mesh that is grounded and tried to diffuse the energy
An intuitive/Naive question would be what happens if you put a better insulator between them. how would dielectric permittivity and dielectric loss affect the setup?
Excellent series on shielding. Can it be fair to assume that its always better to shield the cage, so that it will provide optimum protection for both magnetic and electric fields ? Also can you demo sources of magnetic fields and electrical fields ? And finally if you could show the effects of using a shielded cable and non shielded cable vis-a-vis interference. TIA and look forward to more videos !!
Noticed you’re using SMAs for everything after BNC adapters, while I’ve been just using BNCs all the way through. Are SMAs better somehow? Or cheaper? They’re smaller and easier to board-mount, the latter of which is rather appealing.
Well on the one side, a thicker coax cable usually has smaller losses (N-type is better than BNC which is better than SMA - the cable attached to these connectors); but this is only important over long distances. On the other side, a thin cable is more flexible (from a mechanical point of view); so for a 50cm piece of cable, you don't want something thick and bulky - that is why I prefer the SMA. Regarding connectors and price - well, my local electronics distributor doesn't even have female PCB mounted BNC; and SMA is more easily available and its just smaller, so more of them can be put in a smaller space.
How do shield enclosures usually get connected to circuit board ground? I’ve never payed much attention to this in equipment I’ve opened up, but based on this experiment I’m guessing a simple jumper wire would be completely ineffective.
Indeed, you don't just have a jumper wire or a single point connection but rather a good connection involves an all around connection to ground. So for a PCB mounted shield, the connection to ground should be done in multiple points, or ideally the shield is soldered all around to the boards ground.
bravo! very interesting video as usual! one question: grounding lane is known in hi-fi world also as potential source of noise, running in the ground because of all oher appliance connected to that... how to be sure the noise we will capture with our shield will go from he shield into the ground and, at the same time, the grownd connection will not draw into the equipment we want protect noise itself? RC cell between our shield and ground plug in the wall? which values? ... a video about that I think will probably be quite appreciated by many people. Thks in advance :)
Ground potential is always relative. In real life large conductive plates have a significant capacitance against Earth and so AFAIK constitute their own ground, isn't it? Thus the grounding is only strictly mandatory for "small" objects (and due to limited lightspeed nothing can be grounded perfectly). As an analogy, this is a bit like a xylophone plate that easily clangs at its frequency when floating, but not when laying on the floor. With bad grounding the situation can be like laying it on a cymbal that by itself will start to vibrate by resonance when excited by certain frequencies. A large conductive shielding behaves more like a heavy solid object that by its own inertia is hard to excite with high frequencies.
I do agree with you if you are talking about electro-magnetic waves - conductive materials like copper will reflect the wave, while ferrites or lossy materials will absorb the wave and turn it to heat. However, here I was trying to discuss about electric fields only - here you need conductive materials and good connections to ground for efficient shielding.
@@FesZElectronics 🕺🕺🕺woow i get a response from FesZ😁. But isnt shielding a way of protecting a circuit from picking up interferences from outside where EMR is the interferences? What i wanted to say in my first comment is choosing a shield that absorbs EMR is better why because your circuit will generate its own emr and it will reflect back to the circuit am just sayinng 😇
Well, if the distance is small, and the frequency is low, you will be in the "near field"; the electric and magnetic fields are separate and not forming an EM wave yet - here it makes sense to treat the fields differently and shield them differently. As an extreme example, the ground layer under a SMPS, even though its conductive, will not reflect the noise, but rather reduce it. When it comes to noise of course its best to absorb rather then reflect, but that's not always realistic or financially viable...
@@FesZElectronics FesZ am lost whats the differnce between electric field and magnetic field? For example your circuit act like two antennas reciver transmitter so can i say that antennas and radars are "electric field" and magnetic field like transformes and indictors??
These basic experiment videos are very unique ones. We all learnt it on paper, but these tests are very impressive. I really like it! Thank you!
This! 👌
@@m1geo ,
Excellent tutorial! It clarifies the ambiguity between electric and magnetic field shielding. Thanks for your effort to make this.
I wish TH-cam recommendation algorithms would take the educational quality into account to promote channels like this one. Anyways, I'm so glad I found this channel!
Thank you for keeping the presentation simple and easy to make the subject understandable....best videos and presentation i have seen in the EMC world...Thank you
Very nice tutorial on 1st principals of shielding. Thank you!
Very good content. The practical approach is very interesting! Keep up the good work!
around 5:00, The PCB material forms a dielectric that makes it a capacitor. That is why the insertion loss gets lower. Better test it with only a copper plate. I sometimes make capacitors for RF filters from double sided PCB. But a very nice serie of experiments. Well done
You and your channel are great! And this video is another outstandingly good video-class for these concepts you presented - magnetic (previous) and electric (this) field shielding.
I’m curious how certain vídeos as these ones were made, the setup and their making-off.
I believe we all would appreciate very much if you could prepare some “making-off” videos, showing the preparation of the demonstrations, the selection of instruments, how they were adjusted/aligned, etc.
Thank you for demystifying, simplifying and elucidating for us several topics.
It would be great if you can comment on how to provide EMI/EMC shielding for INS module where roll pitch and yaw are measured. And only yaw value gets disturbed a lot when testing is carried on a Rate Table.
Great demonstration! A question: Will the transferred field be affected if you add the grounded plane close to the source plane, but outside not between the planes, as demonstrated? Could you test this? I was speculating that crosstalk and EMF could be improved in a PCB just by adding grounded copper tape to the surface with a thin varnish between the tape and the pcb.
Great video, thanks FesZ!
So tin foil hats actually amplify the mind control beams?
Underrated comment 😁
Not if you wear them with the inside out, but with the outside in, they magnify pi squared power.
Great video 👍🏻
Maybe it's worth mentioning that the return path of the ground also highly effects the attenuation of the signal.
Ideally you want to make that as short and direct as possible to the source (the sending plate in this case)
Especially in the MHz region.
You are right - the shield connection to GND, as well as the GND to noise source; or signal reference connection is important. I guess this can turn into a much more detailed discussion when the ground its self is not very uniform...
@@FesZElectronics Correct, or maybe rather a can of worms, hahaha
Another fascinating, although simple, experiment. The results were not a surprise, but I have never seen the results with my own eyes (or taken the time to do it!) So, thanks Fesz. I do suspect that the thin metal shields (at 3:03) will not attenuate H fields too well, but I wonder if you would be interested to investigate that claim?
Well, I did look at magnetic shielding a couple weeks ago and one of the tested materials was a tin plated copper PCB. The size of the "shield" was much larger than what I was using in the Efield experiments mainly because of the size of the coils needed to generate and measure the magnetic fields, but effectiveness should not be related to size, I mean, the shield should cover the noise source (or the sensitive circuit) but as long as this is achieved if the shield is bigger will not make it work better. I'm not sure if that was what you are expecting.
I am looking to hide a box of gold from a metal detector, how might I do this? From your video it seems like I might be able to somehow create a mesh that is grounded and tried to diffuse the energy
An intuitive/Naive question would be what happens if you put a better insulator between them.
how would dielectric permittivity and dielectric loss affect the setup?
Great video, excelent explanations. Thank you!!
PS. Mulțumiri, și salutări din Texas ;)
Mersi mult! Ma bucur ca va place! Salutari si numai bine!
A very nice demonstration
Is it possible to ground the whole body of an airplane (like the grounded plane you did) to make an airplane stealthy?
Excellent series on shielding. Can it be fair to assume that its always better to shield the cage, so that it will provide optimum protection for both magnetic and electric fields ? Also can you demo sources of magnetic fields and electrical fields ?
And finally if you could show the effects of using a shielded cable and non shielded cable vis-a-vis interference. TIA and look forward to more videos !!
S-tier. Thank you for your work.
Noticed you’re using SMAs for everything after BNC adapters, while I’ve been just using BNCs all the way through. Are SMAs better somehow? Or cheaper? They’re smaller and easier to board-mount, the latter of which is rather appealing.
Well on the one side, a thicker coax cable usually has smaller losses (N-type is better than BNC which is better than SMA - the cable attached to these connectors); but this is only important over long distances. On the other side, a thin cable is more flexible (from a mechanical point of view); so for a 50cm piece of cable, you don't want something thick and bulky - that is why I prefer the SMA. Regarding connectors and price - well, my local electronics distributor doesn't even have female PCB mounted BNC; and SMA is more easily available and its just smaller, so more of them can be put in a smaller space.
Thanks for the posting 😊
Excellent proof of concept.
Very good video. Thank you.
Excellent video. Enough said.
How do shield enclosures usually get connected to circuit board ground? I’ve never payed much attention to this in equipment I’ve opened up, but based on this experiment I’m guessing a simple jumper wire would be completely ineffective.
Indeed, you don't just have a jumper wire or a single point connection but rather a good connection involves an all around connection to ground. So for a PCB mounted shield, the connection to ground should be done in multiple points, or ideally the shield is soldered all around to the boards ground.
Super useful! Thanks a lot! 👌
Very interesting, Thanks.
bravo! very interesting video as usual!
one question: grounding lane is known in hi-fi world also as potential source of noise, running in the ground because of all oher appliance connected to that... how to be sure the noise we will capture with our shield will go from he shield into the ground and, at the same time, the grownd connection will not draw into the equipment we want protect noise itself? RC cell between our shield and ground plug in the wall? which values? ... a video about that I think will probably be quite appreciated by many people. Thks in advance :)
Absolutely wonderful.
thanks for this you really answered my question i gat
thank you
👍
Great content. Thank you.
Very good video
Thanks..!! nice information..!!
Ground potential is always relative. In real life large conductive plates have a significant capacitance against Earth and so AFAIK constitute their own ground, isn't it? Thus the grounding is only strictly mandatory for "small" objects (and due to limited lightspeed nothing can be grounded perfectly).
As an analogy, this is a bit like a xylophone plate that easily clangs at its frequency when floating, but not when laying on the floor. With bad grounding the situation can be like laying it on a cymbal that by itself will start to vibrate by resonance when excited by certain frequencies. A large conductive shielding behaves more like a heavy solid object that by its own inertia is hard to excite with high frequencies.
Nice.
Hello from Brazil.
Your videos are excellent.
I have difficulty in the English language.
Add Portuguese subtitles.
Maybe try in the settings right under: 'Subtitles - Automatic translation - Portuguese'
It depond of the type of the shielding some material reflect and some material absorbs
I do agree with you if you are talking about electro-magnetic waves - conductive materials like copper will reflect the wave, while ferrites or lossy materials will absorb the wave and turn it to heat. However, here I was trying to discuss about electric fields only - here you need conductive materials and good connections to ground for efficient shielding.
@@FesZElectronics 🕺🕺🕺woow i get a response from FesZ😁. But isnt shielding a way of protecting a circuit from picking up interferences from outside where EMR is the interferences? What i wanted to say in my first comment is choosing a shield that absorbs EMR is better why because your circuit will generate its own emr and it will reflect back to the circuit am just sayinng 😇
Well, if the distance is small, and the frequency is low, you will be in the "near field"; the electric and magnetic fields are separate and not forming an EM wave yet - here it makes sense to treat the fields differently and shield them differently. As an extreme example, the ground layer under a SMPS, even though its conductive, will not reflect the noise, but rather reduce it. When it comes to noise of course its best to absorb rather then reflect, but that's not always realistic or financially viable...
@@FesZElectronics FesZ am lost whats the differnce between electric field and magnetic field? For example your circuit act like two antennas reciver transmitter so can i say that antennas and radars are "electric field" and magnetic field like transformes and indictors??
Thanks. Interesting. Subscripted!
Hig
Great vid, thanks very much. Great job