im 68 now and worked in cambridge from the early days of hifi , and mains noise has always been a problem , the main companies like MK.. Crabtree ,..ect Have ALL cottoned ON to the money to be made selling Gizmos wall sockets with inductor filters added , and expensive power stations that claim noise reduction .but it can come at a price like altering the impedance [RAISING ] when it better to lower . they may work but if you are into hifi there is a trade off in sound quality . you can loose dynamics .. banks of plug sockets can be a big problem with magnetic fields running around . also. i think its cheaper to get a dedicated mains put installed off the ring , like 30 amp cooker thats what we done years ago , thanks
Yes indeed I have found dynamics being compressed with some filters.I have a separate ring for the hi fi , and the other socket bank is separate too,.All in the same fuse box, so they all share the same buzz bar, but it sounds fine.I just get intrigued by technology and like to play around with it all.
I have completed my tests. A 8 uH coil was wound on the mains cable along the length on the cable. 6 metres of circa 3 amp cable. The measurement made using a Peak LCR 45 at 200 kHz. Signal generator Pintek FG52 giving 8 Vrms sine wave. At 5 MHz the reactive impedance 2Pifl = 250 ohms more or less, this makes it a reasonable load. Measurements 1400 mV signal generator on or off. A slight rise at 3 MHz to 1450 mV which dropped either side. Seeing as the cable was being bombarded with RF waves I would expect more. If you want to test this unit get a standard cheap mains strip. Plug things in, I used a microwave oven and Ethernet on the mains.. I doubt if anything you do will change any reading much. How close to the incoming supply will give a lower number ( near to main fuse box ). I speculate it measures mains impedance. Having a low mains impedance is very helpful it must be said. This common mode test is harder to do. Whilst it's very hard to prove how much RFi is in your environment a test device should show increased noise. In my location using my best efforts I could not register increased noise pollution. The unit says Line EMI meter and a little symbol like a hedgehog. It has no maker information on the case. It looks like the unit at the start of the video.
I forgot to say. I tested a Tasima unit many years ago mentioned above in read more. Whilst being of very humble appearance it works well. The designer told me it's tuned to 70 kHz which is a typical problem frequency ( 50 to 100 kHz effective range ). To put this into perspective. As best I know all hi fi filters are modified washing machine filters in layout. Some call them Pi filters which isn't quite right. Whilst a washing machine filter would be hopeless the principles are good. Given the choice between Tasima and this EMI device I would choose Tasima. The trick the best filters perform is to reduce the noise whilst having very low DC resistance. In a nutshell that's it . Washing machines whilst not hi fi are very serious pieces of engineering. They don't fit filters for fun.
I have some measurements now. Unit says 1300 mV or -45 dB below mains voltage. Above 2 kHz I have 120 mV or about - 67 dB. That means over reading by more than ten fold. Above 30 kHz 40 mV. The only region I can get 1300 mV is 250 Hz to 1.5 kHz which isn't what we want to know. The analogy is reading infrared when wanting ultra violet readings of light. Even 10 kHz by analogy is viable spectrum. I have a specialised opto coupled oscilloscope to do this. Don't try it yourself.
Hope this works. Graphs of measurements. 1 Hz to 4 kHz shouldn't interest the device, seems it might. 2 kHz up 120 mV ( - 67 dB ) 30 kHz up circa -75 dB ( 40 mV ). - 45 dB is claimed level or 1300 mV. 8 MHz band limit. [img]i.imgur.com/HEcfJZK.jpg[/img]. I haven't used Imgur for ages. Hope it is still viable. You might have to copy and paste.
I forgot to say. I have made attempts to do common mode testing. As yet nothing shows up. This is harder to test.. The common mode inductor I have tried is 20 turns of wire at 5.5 MHz onto the mains cable into the unit. I will go to 200 turns to a matched impedance at lower frequency. I expected to see something, absolutely nothing. The beauty of this test is it is like real life as it has no ferrite enhancement. I imagine they would find common mode testing harder. Enough to say I have doubts. The unit makes no attempt to say if differential or common mode. I have 8 V rms to use. It should do something surely? I have 36 ohms impedance on that 20 turn coil and 50 ohms output impedance. I should be getting about 5 Vrms. To be clear the display didn't change at all.
I'm going to take out the filter bank in the back room and just have normal sockets.If I had the money I would try a few more filters or even a isolation transformer.
@@nonsensicalchild have you seen the isoteck plugs and the russ Andrews 1s just looks like a plug no cable and from what I can see works amazing. Russ 1s 55 quid and isoteck 1s are 110. You reckon there worth a go???
@@ryanwaterworth7055 didn't notice much difference but that could mean they had just worn out.I remember the russ andrews silencer widen the stereo field with an earlier hi fi but not with my current set up.
I have just received my unit. Instead of doing what most people do I have tried to make my house noisier. The results are totally unchanged!!! I switched off my either net to do the opposite. Absolutely no change. As said that gives me 7 dB usually on my spectrum analyser. I suspect as pure conjecture this device measures mains impedance. DC resistance even? Whilst this is highly commendable it is not noise, but is useful in the fight. I put a 4.4 uF capacitor across it ( correct type ). Absolutely nothing. 1/2Pifc if wanting to calculate it. Most mains cable is 80 ohms at RF and DCR of mains is 0.1 ohms best case. When I used a NAD3020 as an additional load nothing!
I would imagine these devices would be most sensitive to Either-net via mains as ENVM is intended to penetrate circuits to deliver internet without cables. If so the device could be indicating interesting but slightly irrelevant reading. On my spectrum analyser the noise floor rises from - 113 dBV to -106dBV when ENVM is in use. This is annoying but not tragic. I have seen really good brands like Monster said to fail this test. Having opened and inspected a Monster RFi filter it seemed to be of very good standard practice. When I do laboratory tests I switch off my Ether-net via mains locally. I will buy a unit as I feel without more knowledge we learn nothing from these gadgets. I noted someone said 10 kHz to 25 MHz. That's exactly what I said somewhere else. I am flattered but not impressed to be repeated. At present this device is like a radio that receives all stations without differentiating which is which. When I looked at test equipment to do this work I thought $10 000 would be a minimum. That would be a cheaper option if wondering. Remember how a thing sounds is the test. Hi fi is a dynamic user of power unlike this tester. If you like the filter is a harbour. If we disconnect the harbour from the sea it might be ultra calm but doesn't do it's prime job any more. These testers would need to load the circuit by > 1000 watts at 230 VAC to fit a 50 ohm standard used since 1929 and devised in 1880 by Oliver Heaviside. If the unit did it would be to hot to handle in 10 seconds.
After watching a few youtube videos, seems like it depends on the default main socket's noise. This guy's house noise level is only around 190 , and when he tests his power conditioner, it reduces to 100-150, so its not much. ruclips.net/video/3qFh1e7razo/видео.html But this guy's house noise level is 1300+ mv and he tests 2 power conditioners, one reduces to 800+ the other one to 190-200, so that's a lot. ruclips.net/video/64VM6Jz4oRc/видео.html This one is the best result, but the power conditioner is also overkill and pricey, normal socket highest is 180 but it's using different device so probably different method of measurement, but the final result is only 25+ ruclips.net/video/mo3_9KVEAOw/видео.html Here in this video its around 250+ and the reduction even using TP1000 is only reducing it to like 190+
Нужно измерить с фильтром и без него ! На сколько этот прибор полезен ? Первое на что обратил внимание что в видео не было не одного профессионального фильтра , так детские которые не чего не фильтруют . После фильтра должно упасть до 5 - 10 значений ,ну и прибор не совсем правильный . У него нет базы !
im 68 now and worked in cambridge from the early days of hifi , and mains noise has always been a problem , the main companies like MK.. Crabtree ,..ect Have ALL cottoned ON to the money to be made selling Gizmos wall sockets with inductor filters added , and expensive power stations that claim noise reduction .but it can come at a price like altering the impedance [RAISING ] when it better to lower . they may work but if you are into hifi there is a trade off in sound quality . you can loose dynamics .. banks of plug sockets can be a big problem with magnetic fields running around . also. i think its cheaper to get a dedicated mains put installed off the ring , like 30 amp cooker thats what we done years ago , thanks
Yes indeed I have found dynamics being compressed with some filters.I have a separate ring for the hi fi , and the other socket bank is separate too,.All in the same fuse box, so they all share the same buzz bar, but it sounds fine.I just get intrigued by technology and like to play around with it all.
It would be useful if it identified the frequencies of the noise.
I have a unit on order now. I suspect the mV shown is after amplification.
I have completed my tests. A 8 uH coil was wound on the mains cable along the length on the cable. 6 metres of circa 3 amp cable. The measurement made using a Peak LCR 45 at 200 kHz. Signal generator Pintek FG52 giving 8 Vrms sine wave. At 5 MHz the reactive impedance 2Pifl = 250 ohms more or less, this makes it a reasonable load. Measurements 1400 mV signal generator on or off. A slight rise at 3 MHz to 1450 mV which dropped either side. Seeing as the cable was being bombarded with RF waves I would expect more. If you want to test this unit get a standard cheap mains strip. Plug things in, I used a microwave oven and Ethernet on the mains.. I doubt if anything you do will change any reading much. How close to the incoming supply will give a lower number ( near to main fuse box ). I speculate it measures mains impedance. Having a low mains impedance is very helpful it must be said. This common mode test is harder to do. Whilst it's very hard to prove how much RFi is in your environment a test device should show increased noise. In my location using my best efforts I could not register increased noise pollution. The unit says Line EMI meter and a little symbol like a hedgehog. It has no maker information on the case. It looks like the unit at the start of the video.
I forgot to say. I tested a Tasima unit many years ago mentioned above in read more. Whilst being of very humble appearance it works well. The designer told me it's tuned to 70 kHz which is a typical problem frequency ( 50 to 100 kHz effective range ). To put this into perspective. As best I know all hi fi filters are modified washing machine filters in layout. Some call them Pi filters which isn't quite right. Whilst a washing machine filter would be hopeless the principles are good. Given the choice between Tasima and this EMI device I would choose Tasima. The trick the best filters perform is to reduce the noise whilst having very low DC resistance. In a nutshell that's it . Washing machines whilst not hi fi are very serious pieces of engineering. They don't fit filters for fun.
I have some measurements now. Unit says 1300 mV or -45 dB below mains voltage. Above 2 kHz I have 120 mV or about - 67 dB. That means over reading by more than ten fold. Above 30 kHz 40 mV. The only region I can get 1300 mV is 250 Hz to 1.5 kHz which isn't what we want to know. The analogy is reading infrared when wanting ultra violet readings of light. Even 10 kHz by analogy is viable spectrum. I have a specialised opto coupled oscilloscope to do this. Don't try it yourself.
Do a video ! It will be very interesting.
@@nonsensicalchild I could do screen shots.
I got the same readings here in the USA
Hope this works. Graphs of measurements. 1 Hz to 4 kHz shouldn't interest the device, seems it might. 2 kHz up 120 mV ( - 67 dB ) 30 kHz up circa -75 dB ( 40 mV ). - 45 dB is claimed level or 1300 mV. 8 MHz band limit. [img]i.imgur.com/HEcfJZK.jpg[/img]. I haven't used Imgur for ages. Hope it is still viable. You might have to copy and paste.
I forgot to say. I have made attempts to do common mode testing. As yet nothing shows up. This is harder to test.. The common mode inductor I have tried is 20 turns of wire at 5.5 MHz onto the mains cable into the unit. I will go to 200 turns to a matched impedance at lower frequency. I expected to see something, absolutely nothing. The beauty of this test is it is like real life as it has no ferrite enhancement. I imagine they would find common mode testing harder. Enough to say I have doubts. The unit makes no attempt to say if differential or common mode. I have 8 V rms to use. It should do something surely? I have 36 ohms impedance on that 20 turn coil and 50 ohms output impedance. I should be getting about 5 Vrms. To be clear the display didn't change at all.
So have you found a solution it's driving me mad now I know I have dirty power
I'm going to take out the filter bank in the back room and just have normal sockets.If I had the money I would try a few more filters or even a isolation transformer.
@@nonsensicalchild have you seen the isoteck plugs and the russ Andrews 1s just looks like a plug no cable and from what I can see works amazing. Russ 1s 55 quid and isoteck 1s are 110.
You reckon there worth a go???
@@ryanwaterworth7055 I had both wish I would have kept them for the video but they were very old , they do wear out.
@@nonsensicalchild did they work
@@ryanwaterworth7055 didn't notice much difference but that could mean they had just worn out.I remember the russ andrews silencer widen the stereo field with an earlier hi fi but not with my current set up.
@nonsensicalchild do you believe the emi-meter and filters from greenwave are something more than a snake-oil?
I haven't tested anything made by greenwave so sorry I don't know.
I have just received my unit. Instead of doing what most people do I have tried to make my house noisier. The results are totally unchanged!!! I switched off my either net to do the opposite. Absolutely no change. As said that gives me 7 dB usually on my spectrum analyser. I suspect as pure conjecture this device measures mains impedance. DC resistance even? Whilst this is highly commendable it is not noise, but is useful in the fight. I put a 4.4 uF capacitor across it ( correct type ). Absolutely nothing. 1/2Pifc if wanting to calculate it. Most mains cable is 80 ohms at RF and DCR of mains is 0.1 ohms best case. When I used a NAD3020 as an additional load nothing!
I would imagine these devices would be most sensitive to Either-net via mains as ENVM is intended to penetrate circuits to deliver internet without cables. If so the device could be indicating interesting but slightly irrelevant reading. On my spectrum analyser the noise floor rises from - 113 dBV to -106dBV when ENVM is in use. This is annoying but not tragic. I have seen really good brands like Monster said to fail this test. Having opened and inspected a Monster RFi filter it seemed to be of very good standard practice. When I do laboratory tests I switch off my Ether-net via mains locally. I will buy a unit as I feel without more knowledge we learn nothing from these gadgets. I noted someone said 10 kHz to 25 MHz. That's exactly what I said somewhere else. I am flattered but not impressed to be repeated. At present this device is like a radio that receives all stations without differentiating which is which. When I looked at test equipment to do this work I thought $10 000 would be a minimum. That would be a cheaper option if wondering. Remember how a thing sounds is the test. Hi fi is a dynamic user of power unlike this tester. If you like the filter is a harbour. If we disconnect the harbour from the sea it might be ultra calm but doesn't do it's prime job any more. These testers would need to load the circuit by > 1000 watts at 230 VAC to fit a 50 ohm standard used since 1929 and devised in 1880 by Oliver Heaviside. If the unit did it would be to hot to handle in 10 seconds.
After watching a few youtube videos, seems like it depends on the default main socket's noise.
This guy's house noise level is only around 190 , and when he tests his power conditioner, it reduces to 100-150, so its not much.
ruclips.net/video/3qFh1e7razo/видео.html
But this guy's house noise level is 1300+ mv and he tests 2 power conditioners, one reduces to 800+ the other one to 190-200, so that's a lot.
ruclips.net/video/64VM6Jz4oRc/видео.html
This one is the best result, but the power conditioner is also overkill and pricey, normal socket highest is 180 but it's using different device so probably different method of measurement, but the final result is only 25+ ruclips.net/video/mo3_9KVEAOw/видео.html
Here in this video its around 250+ and the reduction even using TP1000 is only reducing it to like 190+
Нужно измерить с фильтром и без него ! На сколько этот прибор полезен ?
Первое на что обратил внимание что в видео не было не одного профессионального фильтра , так детские которые не чего не фильтруют .
После фильтра должно упасть до 5 - 10 значений ,ну и прибор не совсем правильный . У него нет базы !