Nice job, made a similar one a few years back to suppress the noise from the dish-washer in our house, when the wife turned the blasted thing on, its was making more noise than an 'over the horizon radar' on HF.....mains filter solved the problem. Subscribed, as i am looking forward to see just how many 'thumbs up' you can squeeze into the next 15 minute video !! 👍👍👍👍👍👍👍👍👍
No doubt someone else has said this but here goes. Red, Blue, Yellow crimp terminals are not for colour coding your connections, they are for different gauge wires.
Yes. I don’t know if that’s universal and I suppose it’s possible that it’s not always, but on these it sure looks to be the case. I paused and zoomed in. maybe that’s why he had trouble crimping. Seems like a useful project though. Maybe one day I’ll make one…
You are indeed correct… although given how cheap and poor quality these were it made little difference. I have since replaced them with good (all the same colour/size) quality connections.
@@M7EUP .Thank you for sharing,good job done. Correct crimping tools, will have jaw slots which are colour coded to correspond with the coloured terminals. Perhaps you could have finished off with a demo with it in and out of line in short time span. 73 de ZL1PO
I built one during lockdown and furlough. It ended up going into a much larger box because of the mains filter was a lot bigger than Ian specified. So I put a 4 gang socket unit directly on the front along with a 30mA trip on the outputs. The rest of the house is on wired fuses and a ""master on/off switch. Incorporated into the unit I added a voltage/current monitor module. Works a treat, noise level dropped by several S points and the addition of 1:1 current baluns at the HF antenna feed and in the shack have brought the noise right down to S1 or 2 depending on band. By the way the crimp connectors are colour coded by wire size. For the wire inside the box you need the blue ones and for the input and out put you need the red ones. The earth might need a yellow for both wires. Use some hot snot or neutral cure silicon sealant to glue down the ferrites.
Great video on an often overlooked subject. I'll be looking into this and trying it out. I also have a Yaesu FT-450D on and EFHW wire and it seems that more often than not, the noise floor is rather high, especially on 40 and 20 meters. Oh, as a side note, I didn't have any difficulty distinguishing between ferrite and Fair-Rite in your narrative, and I'm not British.😂
Thanks Howie, It’s cause a bit of a stir has the old Ferrite / Fair-Rite for sure Check that you actually have a mains borne RFI issue before spending any money doing this.
"Two fools, one thought!" - did the same with my setup. Was able to receive 100mW packets from our TRSI-2 satellite on 500km orbit with a small omnidirectional antenna. No switching regulators of course, clean copper&iron transformer, linear regulator etc. I was living in a valley in the countryside: spectrum clean as a monk's concience! A good LNA and a sharp bandpass filter squeezed the noise down even further.
A better way to mount everything in that box is to cut a piece of 2 or 3mm plastic sheet to fill the bottom of the box, this can be screwed to the rows of mounts provided in the bottom of the box using self tapping screws, then either (for the filter) screw it to that sheet, and for most of the rest, drill holes for cable ties. This way everything is tied in place without any holes in the bottom of the box.
Thanks for your video. I'm not into HAM radio but it can be useful for my lab or problematic (not very well filtered) HiFi. One thing: You screwed the stranded mains wire directly into you screw connectorblock ("Lüsterklemme" as they are called here). You should (must) use ferrule to prevent the screws from damaging the strands. Furthermore these connector blocks often are rated only for 8A or 10A, so you need to replace the fuse in you plug. The other solution would be to use elevator clamps or other types were the screw isn't screwed onto the wire directly. Or use WAGO clamps, 221 or 222 series.
Thank you for the comment. As I’m sure you’ll appreciated, when making videos like this it’s often a learning curve and often difficult to capture and edit the entire process. I should really do a “follow up” video to this as, like you say, it needed a few tweaks once proof of concept was established. I have replaced the connector block with ferrules and have also replaced the push connectors with more appropriate and better quality ones which have been soldered and heat shrunk.
Cool demo. Would have liked to see you unplug it from the filter and direct into the wall afterwards though just to show back to back readings.... For me, my RFI issues on certain bands come and go over periods of time...
Sadly most RFI issues are received via the antenna and not the mains which is why I always suggest running on battery with the power off to ensure that mains RFI is the cause. If external RFI is an issue then have look at this ruclips.net/video/lP3RiX2KkRQ/видео.htmlsi=BjPFAqq-dX8568On
They are colour coded because they use different size of wire. Might be a good thing to place the ferite cores 90 degrees off of each other. Don't know if it applies to noise filtering. But at least for RF it does. But a great project. There is some video where they say do not connect earth to your devices but make your own. Isloating.
When laying out a case, use blue painters tape around the outside, then you can mark up as much as you want with a fine pencil, drill / cut as required, then peel to leave a defect free surface.
Past the filter, you have a very long extention cable that would pickup noise. If one would slide metal braid over the cable, i would think you could have a little bit more protection.
Apologies. If you do, stick to the instructions in respect to parts, number of turns etc. I’ve seen so many people try this and add extra turns or get alternative Fair-rites etc and it just doesn’t work.
in-between the mains filter and the 6 gang extension i also wound a couple of type 43 and type 61 240 ferrites probably overkill but had a couple spare.
The protective conductor should definitely not be twisted, only the phase and neutral conductors, and with multiple strands, for example, 8 strands of 0.25 square mm each. Here's how: take two strands of phase and neutral conductors, twist them together counterclockwise, then take another pair and twist them clockwise, alternating between counterclockwise and clockwise. This must remain symmetric throughout. Afterward, you should have four strands made up of phase and neutral. Twist two of these four strands clockwise and the other two counterclockwise. This ensures symmetry. As shown in the video, you can simply get double the number of ferrite cores. The protective conductor should be separately filtered using a ferrite ring, placed as close as possible to the filter's input. There’s also another reason why the protective conductor should not be twisted together with the others: doing so induces voltage on the protective conductor, which can lead to interference. The filter itself already induces voltages on the protective conductor since capacitors in the filter are connected to it. Additionally, every device connected in any way to the radio equipment must pass through the filter; otherwise, ground loops will occur. This includes computers or any other peripherals, as they can introduce differential voltage issues.
Thank you for your input. As you’ll see from the other comments it’s a very debatable little project and something that can always be improved upon. I built the filter to the original design but I’m sure that it can be developed further.
nice work, yes they do work well, dint do a thing for my shack, as it's the same on battery still there even with both and mine mains off, so my problem is airborne. although you mentioned something your video that may shed some light why mine didn't work, I never broke wind and left for 10 minutes lol.
I wonder how a filter system like this would work for audio, or test instruments, such as an oscilloscope. I get a lot of interference, when trying to trace small signals, where I need a lot of channel gain.
The problem with this approach is that any piece of equipment connected, which is also connected to earth ground (antenna ground) bypasses this device. I built this and while it helped, as soon as the radio earth ground is connected the noise returns.
I can't earth my radio anyway, my shack is on the second floor, any earth wire would act as an antenna, I have ferrites on my equipment and have a fairly low noise floor across the bands.
I built a couple of these a few years ago, extremely effective, fwiw I don't have the join at the connector block. the output cable going all the way through the ferrites. A similar reduction in noise to yours on 40m in particular. I used similar ferrites on the phone line (VDSL) and the LNB cables to the satellite dish. Just to address a few comments, the box SHOULD NOT be metallic, and a UPS will not generally help with common mode RF. 73
Good question. Essentially in a lower frequency range, an increased number of turns can provide a greater reduction. However, as the frequency increases, the performance of a higher number of turns can be worse than a lower number of turns. It’s a bit of a balancing act, but for the purposes of HF and VHF radio in relation to mains borne RFI the original author will have calculated to optimum performance. This is why I also state to only use the parts listed, from the cores themselves to the gauge of wire Hope this helps.
@@drmisfit 1) twisting wires will reduce the magnetic flux between them and so the EMF pickup, this is why low-level signal cables should use twisted pairs 2) with controlled twisting we can have well defined inductance/capacitance per unit length, making a transmission line with a well defined characteristic impedance.
Excellent video! I do have S9 noise on most bands, most of the time. Only problem for me will be how to get hold of the parts in this part of the globe! 73 Jon, VU2JO
@@M7EUP That advice has been given to me by all my local Elmers as well. But I have not invested in a battery for the shack yet. Home inverter has couple of large batteries. Unfortunately I had not planned that to be near my shack when I built the house! 73
@ it’s a worthwhile investment, even if just for testing purposes. You don’t want to be spending a load of money building a filter if all your noise turns out to be a dodgy transformer in a street lamp outside.
Just so you can complete the test why don't you borrow a battery. It's alot of money for a one off test. It doesn't have to be lithium a reasonable ah car battery will do. Save your money for good quality coax......
Thanks for the comment, most modern power strips contain MOV’s ( Metal oxide varistors ) to some extent to regulate power surges. However, in HAM radio application the transceiver is not usually directly connected to the mains power supply. It is fed 13.8V DC with a power supply unit, thus adding another level of protection.
@@M7EUP Time to do something about it then! Using crimps that are the wrong size can have pretty dramatic implications for safety and all that, what-a-ma-with the sparks and flying leads and such!
So it is basicly two rf chokes that converts two ranges of frequencies into heat? If you have a variety of ferite cores stripped from power supplies or inverters, can you not just measure the inductance to calculate the approx frequencies ranges that will be filtered?
The idea is to cover the frequencies that are most commonly used in HF and VHF and help to keep those “clean”. What you suggest is valid but specific to the interference for each individual.
If you have an idea of what your interference is caused by in terms of amplitude and frequency, then that's certainly a valid choice of method. Don't forget about common mode filtering if you're working with noise induced on your power lines when they were running parallel. The twisting can help with that, but is generally not a great way to do it unless you're working with signal level wires. When choosing your cores, make sure you consider more than just the final inductance you're aiming for. The final inductance of your choke will depend on the wire size you use, the amount of insulation between the core and the wire strands, the size of the core, the exact permeability of that core (ferrite vs moly powder comp vs moly film composite etcetera), and how many turns. Since the wire insulation distances the wire's conductor from the inductor's core, you can see why we use magnet (lacquered) wire on magnetics. Any inductor, whether it be from a clamp on ferrite core or a tightly controlled winding benefits from even spacing around the core. Don't cross the direction of your wires, as that'll cause more harm than good. Don't try and combine your CMC and your low pass filter chokes!
A little portable AM/SW radio works to locate your RF noise makers, then move all that crap into the _basement_ and then you'll have a LOW "noise floor"!😋
I would have held the toroids in place with a bit of hot glue. Also if using a screw connector block, I would have crimped ferrules on the ends of the stranded wires. Other than that, great job. 👍 👍 😁
You’re absolutely right John and that’s exactly what I did before permanently installing it in the shack. Great advice. Always happy playing with the old hot glue.
@@M7EUP I prefer the Wago connectors over screw terminals, and you can get in-line ones as well. They're good for high loads as well. I'm a returning operator who needs to find the time to get my shed converted into a shack, as my wife does not want the equipment in our house. Because of that, I'm only operating on 2m & 70cm at the moment, but I may see you on HF sometime in the future. All the best, G4MLZ.
That’s a great question. If you can visualise any interference travelling up one wire and back down the other in opposite directions like ripples heading towards each other in a pond, when they meet they stand a chance of cancelling each other out. Twisting the wires increases that chance. That said, anecdotally people have built these without twisting the wires and seen little difference in performance. However I would always give myself the best chance of reducing any RF so I add the twists.
Excellent device. Are you really sure that on the fairrite website that is the correct ferrite despite the wrong picture ? I don't want to end up with the wrong one !
Filters and HAM are outside of my knowledge base. Meaning, I do not have the ability to design the Ferrite filters for USA/120VAC/60Hz/Broad bandwidth general use EE hobby lab frequencies. However, I have a spare can filter. I would think that just adding it on the power plug strip would help somewhat = better than nothing. Thoughts/suggestions? Thanks. Cheers. Hmm, now that I think of it, the filter may be limited to 6A. I will need to check that. The wall socket is up to 15A. Depending on the DUT and the test equipment being used, I could be pushing 15A.
I would say it entirely depends on your need/application The filter (silver box) is rated up to 250vAC ✅ filters 50 & 60Hz ✅ The cores and number of windings is selected for RFi elimination on the Amateur radio bands… 1.8 to 10 MHz and 14 to 50 MHz.
I have power line noise but not via the mains. Is this because the transformers isolate the noise and only the antenna and possibly coax are receiving direct from the powerlines but not from the mains power? I've tried on a battery, no difference. I tried putting the noise canceller aux antenna close to a mains lead but it doesn't help. best result was a large loop of wire in the gdn as the aux ant for the canceller. driving around I get loud noise around those smaller power-lines whenever I pass them. There is a hydro electric power station around 3 or 4 km away, sometimes the cables are buried below ground for some sections. I don't think I will get any help from the electric company in France.
It’s worth trying to report the RFI to the radio regulator. I’m not sure how it works in France but in the UK OFCOM will actually investigate and order companies to improve. It’s important for not just Amateur Radio operators but for all types of communication including emergency services. Give it a try.
@@M7EUP I called the power company about getting estimated bills. They came and replaced the meter. The noise disappeared and I got regular bills again.
Certainly the first component, the silver box mains filter, would help with any mains borne noise… however the torriod/ferrite cores are made to eliminate noise on frequencies used by amateur radio operators so whether these would be a benefit is not something I could answer, as I have no experience in studio recording.
Hi mate, that's a great video you posted there, thanks for your efforts, i have a different problem over here, i seem to be causing electromagnetic interference in the power lines of my house and can hear myself coming in through the speakers of my amplifier for my entertainment unit and i seem to be knocking out the network cameras every time i tx, would this device help with this ? I put the interference down to bad filtering n cheap Chinese products as it only occurs in a could of appliances.
In all honesty a mains filter is not the place to start. If you are causing EMC like that the you really need to get to the bottom of why. It would be helpful to know your set up to help work the problem. Radio, PsU, coax, antenna, antenna location etc etc
@@M7EUP Thanks for getting back to me, I am running a SE HP360 XP broadband antenna on a 9 meter pole, running into a MFJ 986 roller inductor tuner, a president p400 27mhz cb and president hr2510 radio., running rg213 coax everywhere . I intend to try grounding the MFJ tuner this weekend with an independent ground stake, i also yesterday grounded the roofing iron and seen a notiaible difference so will see how grounding the tuner and station goes. If the filters you describe work could be handy for handing out to people I am interfering with, had one such complaint a while ago and replacing his clock radio fixed the problem so i pout it down to poor filtering in the device. havent had any complaints since then.
I think perhaps a mains filter would be an expensive way to go in this instance. Maybe have a box of torroid rings ready and wrap the power leads of affected items through them.
@@M7EUP have tried that on the network cables of the surveillance box already for the cameras, that did not fix the issue, the power cables for the mains being high voltage, i have been advised not to do this to mains cables as it may cause heating from the inductance created. So just asking again, would you mains filter help the situation and would grounding my tuner and my station help also ?
@@thearchitect4726 it’s a tricky question to answer. In your initial question you stated that you were hearing your transmissions through audio equipment which would lead me to suspect that the interference was being captured via a receiver rather than the mains power supply. Similarly if you’re getting issues with broadband etc. The only way of knowing is isolate your property power supply and run your radio and affected equipment on battery power. If the problem is still present it’s more likely to be an issue with the location of your feed line and antenna. You could certainly try grounding all of your equipment although this is not a “cure all” for many issues. As an experiment try transmitting with the radio outside of the property on battery power a with a shorter length of coax that is away from the property.
How'd you determine what number of twists to use per foor? Why did you include the PE/ground wire in the twisted pairs? All my knowledge of circuit design (which is mostly limited to high performance amplifiers) tells me one should not twist mains wire for normal use, and if one *does* twist it to reduce the coupled noise, then it should be just the L/N wires and no more than a couple of twists per foot, say four to five. I'm eager to know what your number of twists per foot was based on, or the reason for including the PE/ground wire in the twisted pair. Or even why you're twisting them at all.
The answer isn’t straightforward. Where low frequency is concerned (audio and below) the theory of the twisted pair effectively creates a situation where noise on one wire is cancelled out by noise on the other. It also rejects interference from outside as both wires cancel out any incoming fields - similar to common mode current on transmission lines. The twisting couples the fields around each conductor in a way that reduces flux leakage. You could look at it like a rudimentary form of shielding where braided coax cannot be used. Most analogue telephone systems used twisted pairs, and in old valve equipment, the cathode heater wires (which were low voltage AC) would be twisted to reduce radiated hum into other parts of the DC circuit. Where you’re looking to suppress RF then twisting the conductors should reduce any RF from coupling into other conductors and reduce crosstalk. So I would assume that the design of the filter was aiming to do something similar, by twisting the noisy mains conductors and reducing the possibility of any noise bypassing the choke and coupling into the clean side. I’m not aware of a formula for determining the degree of twist but from past observation it’s around 6 twists per inch… Or in other words I followed the instructions exactly as they were written by the original author. As for the emergency earth there is an argument to say that this not should pass through the ferrites and have its own filter. However I again refer back to the original plans.
A very good way to stop interference is getting an uninterruptible power supply as most of the time these are charging batteries and powering off of them in such a way that it’s being inverted again to a pure sideways with no interference I would highly recommend using singles which are single inch related cables or try rated singles instead of stripping back flex but it depends on where you get your supplies from as many eBay sellers will sell these cheaper than the roller flex costs. There may be an issue with how tight the windings are round the ferrite because it would count as group so the current rating may need to be adjusted but I think it’s fine based on the size you have used (you probably looked at all of these things, but just didn’t mention it on the video
Most, if not all uninterruptible power supplies do not work as you describe. They charge a battery and keep it charged. The mains output is just fed through from the mains input through a relay. If power fails, the square-wave (of modified square wave at best) inverter kicks in and the relay changes over to the inverter. So, there will be absolutely no clean power from these units.
@@meindertsprang7491 however you need to get ones rated for IT equipment and sensitive service stuff. They are amazing they have really pure power. They’re quite expensive new but they pop up on eBay all the time data centres replaced regularly so they don’t fail they use a transformer based design so a square wave would not drive the transformer properly
Great video, but I think you are making a mistake with crimping choice! Colors on plastic isolated crimp connectors are to match the wire gauge and NOT the wire insulation colors!
If that noise is being picked up via the mains supply then yes, you should see an improvement, however, as I say, test your radio with a battery and the mains power completely off in the house. If the noise goes then this will help.
@@M7EUP More specifically, common mode chokes only work for common mode noise, which means the phase and amplitude needs to be the same on both N and L. That generally does not apply to or is not the case for noise generated by equipment directly hooked up to the power lines, as they either have a CMC on them already as a required measure, or do not produce truly common mode noise. Common mode noise is primarily present when that interference is *induced* on those wires simultaneously and when they run in the same direction of current flow. The common mode interference would hence be filtered out by a common mode choke where one of the lines runs 180 degrees out of phase -- meaning, the current flows in the opposite physical (N-E-S-W) direction from previously. That would essentially mean having one of the conductors enter the two-wire inductor from the opposite end, as to invert phase. In reality, most CMC's are built in a way where you can wire them L/N in and L/N out without needing to worry about it. 🙂 Feel free to ignore the latter explanation if this sounds exactly opposite of the actual way it should be -- that means you're already thinking about magnetics, and this physical world explanation doesn't apply to you.
Correct. You would need to add a third fair-rite for sub 1MHz… I couldn’t tell you the material or number of windings right now but it’s fairly easy to look up.
Good grief ! Some of these comments lol. I tried my radios (yes I have multiple ones all bought second hand but my 450D I love best) on batteries and still have a high noise floor. Unfortunately behind my shack is a new housing estate and I suspect that the noise is from there. Last couple of years lots of solar has been appearing as well which has made it a lot worse. Ah well I will have to go mobile or move. 73 M7BLC
Interesting that the mains filter does not actually filter the earth, as they are connected directly via the chassis of the mains filter, it appears. So the mains earth filtering is non-existant it seems. Odd to bother mains filtering the live and neutral then allow it to be in contact with the unfiltered earth in the torroid wrappings, plus the torroid windings need separation between the start and end of the windings...otherwise you just undid the point of the windings, because they are touching each other. One other thing on a different point ....How do you intend providing an RF earth in your shack...out of curiosity? I ask as some years ago when Ian released his RSGB videos, myself and others pointed out the error of his ways in doing this, his repply to me was to consult an electrician, as he wasn't one, with regard to RF earthing dispite having a viseo about it advising people. Myself and another electrician who were amateur radio operators exchanged a few emails with him regarding his very subject, and his mains filter, plus TNS, TNCS ans TT earthing systems, and the dangers therein. Still if it works.....???? Forget the safety I guess???
I am nowhere near qualified to give you a scientific answer to this but on a basic level… The mains filter filters current, up to 240v, 60/50 Hertz. The earth wire doesn’t carry current so does not get filtered at this stage. It is simply attached to the case of current bearing filter for safety. There is no break in continuity of the earth wire from plug to socket. The earth wire DOES pass through both Fair-rite cores which deal with stray RFI. Finally, RF-Earth is an entirely separate issue and is dealt with in the normal ways, this eliminator has nothing to do with RF-Earth.
The Tacima CS929 block is a budget filter block, however the filter board has an earth-line choke amongst other things if you want to see if it brings down mains noise any further.
@@M7EUP I understand that RF earth is a totally different point but was curious exactly what you did for your shack,,,,,and just mentioned Ian's view on it for completeness of RF in the shack. Good informative video though on a subject that causes some people difficulty...and I am glad this worked for you...even with an unfiltered mains earth. At least the earth has a choked effect at the frequencies mentioned in your video and that will help and some people put a few clip on ferrites on the mains side of this filter near the plug and actual filter too, as all exposed cabling is liable to RF pick up especially if the cable is of a resonant length or multiply resonant lengths on certain frequencies.... The subject is vast and once you succede in filtering the mains incomming, you then have the issue of self generated RF within the shack and then antenna feedline RF pick up, passing stray RF via the coax feedline braid into your equipment cases as they are connected to the coax plug directly and are negatively earthed via any transformers that power the radio equipment thus the RF enters your filter backwards if you like.........and ...on....and....on we go....ha.... Good video though and will help most folks out. Enjoyed it....and it gets people chatting....about it....especially if it is affecting their hobby and other household equipment... This doesn't include RF earthing coax outside of your shack with a ground/earth rod as now you will introduce a potential voltage difference into your shack if a mains electric fault developes within your home..... ha...ha.... crazy this hobby..... My next reply will be made available in hardback from most good (or bad) book shops...ha.........Cheers.
First thing to check is your own power supply and household electrical me by switching off the power at the fused box and running on battery. If it’s in the home you then need to narrow it down to a specific item. By turning on circuits one at a time. I’ve heard of laptop chargers causing interference on 160 and 80 but it might not even be in your own home.
Actually no. This phenomenon is common mode probably from the antenna shield. Could be a bad connection or a significant amount of RFI externally. What antenna are you using. Thinks to check: 1: SWR (is there a problem with the antenna) 2: try a different antenna 3: it’s common practice to add a common mode choke balun at the shack end of your coax before it goes into the radio.
@@M7EUP The antenna is a glass fibre moonraker, the power supply is near to the transceiver and was only around 25 pound new for a CB . I did wonder about upgrading it for a low noise type . From the very north of England I have been into Russia, Germany, Hungary, France etc on 20 watts.
@@union310 I've got the same radio. Make sure the RF gain isn't set high ( that just amps noise!) and add a common mode choke right at the radio. Any coax braid between the radio and antenna will pick up all kinds of stray RF noise like an additional "random" antenna element without using a choke. The channel "The Smokin Ape" has tons of common mode choke videos and tests, really easy to make. You'll want to use a mix type "31" toroid core like a FT240-31 toroid ferrite core if you can, as the 31 mix works better for the G90's full band range vs say the more common FT240-40 type 40 mix which falls short in the 40m and 10m bands. That and 1-2m of some cheaper coax jumper like RG-58 or even RG-142.
I suppose the amount of turns are the most important , I’m just waiting on the fairrites to arrive, I had some Perspex left over I mounted the filter to that with some pcb chassis mounts and secured the Perspex to the box
Any particular reason for building a filter and then popping it in a plastic case which will propagate magnetic fields beyond the case dimensions? Might a grounded metal case reduce magnetic fields and improve the filter’s overall performance?
@@M7EUP That seems counterintuitive, but I'm more DC (audio) than RF, so I'm not entirely surprised that weird stuff(TM) might happen... On the other hand, though, RF stuff is often in cans for exactly this reason... 🤔
Clearly you didn’t watch the video. The Mains filter is for Mains born noise. The clue is in the title and the instruction to “test on battery power with mains power turned off to first establish the source is FROM THE MAINS SUPPLY”
For the purposes of Amateur Radio (Ham Radio) we do use isolation transformer for a number of things like impedance matching and choking. You’ll hear us using terminology like 4:1, 9:1, 49:1 etc or 1:1 in the case of an in-line choke. But these tend to be on the antenna side of the radio and not the power side. Essentially the build in the video is aimed at removing unwanted RFi from the power supply and targets specific frequencies that affect us.
getta better crimp by leaving the wire strands straight rather than twisting them. (better than my spelling.) Might be a hard habit to break. *lights cigarette*
@@M7EUP I bought some cheap ferrules and a cheap ferrule crimping tool. The ferrules are fine but the crimping tool does leave a slight star shape profile instead of square. It still passes the pull test though so it's just acceptable for hobbying.
@@M7EUP The colours designate size of cable NOT earth, neutral, live . Probably why you had issues with crimping them. Although I don't recommend cheap connectors either.
Is mains electricity is going through a metal box can work if it’s earth but a plastic box is safer because it will be classed to double insulated so it’s just means if there is an earth fault you can’t get a shock if something goes wrong from the enclosure
I built one of these about 5 years ago. It makes absolutely NO difference to the noise floor. Shutting down the entire house supply and using a battery makes no difference either.
Unfortunately if shutting down the house supply made no difference then by definition the “noise” isn’t from your mains supply and this filter won’t work for you.
@@M7EUP good video all the same. Nice to see something that's achievable as opposed to someone going out and dropping £500 on a random antenna and mounting system for a 20 minute video.
I remember making hundreds of braid-breakers to fit right at the back of TV sets to reduce the timebase harmonics radiating form the TV antenna feeder. Bonus was it formed a high-pass filter. I think I used a design from TT or an RSGB book? Long time ago now. Gave them to neighbours up and down the street and it made a huge difference on the lower bands.
Are you aware that in Australia the thumbs up sign is an insult relating it to 'stick it up your arse"? Had buil5 a similar device in sth3 states some 35 years ago. I would have used here in the EU but the COR COM filter is rated for only 120 volts 60Hz. Time to order these parts and build another filter for use in Europe. Also have issues with corona discharge from a 7kilovolt to 220-380 volt three base pole mounted transformer. We are only 1/2 mile from the ocean here and that salt builds up on the insulators. On damp mornings the noise floor is unbearable!
The aussie stick it up your arse thumbs up thing is really only a problem if you go wagging that thumbs-up vertically. I'm sure no sane aussie's over here getting insulted by a kindhearted "Great job!" with a thumbs-up 😀
@@BTW... I am Greek and living in Greece and it’s been only in the last ten years that the middle finger has gained as a vulgar sign. For many decades the Mouzoma aka the palm of five open fingers in towards one face was the insult gesture of choice. About eight years ago the government here passed a law prohibiting the use of that gesture by drivers on the road and supposedly it’s an offense that carrys a fine.
Lol all the yt experts are commenting on your video mate......only a radio boffin invented it so yt commentors shut the front door up wingeing f#@×... What size are the oval cores please mate I need to build one as farmfoods fans proper kill me with rfi..excellent video and very educational
Some people just need to have their say, welcome to RUclips. All the individual items are listed with links in the description. If you go to the link for the oval cores you’ll be taken to the mouser website. Click on the Data Sheet link from there for the full specification.
@@M7EUP I appreciate that, it just sounded like you were using incorrect terminology. That's all. Was there any particular reason to use that brand over another?
@@DelticEngine yes, because as GM3SEK says in the presentation and the documentation it is vital to use only the specified parts and part numbers listed. Alternatives will have different results. It’s really important for people to follow the instructions to the letter and that includes actually establishing the main borne RFI is actually an issue by isolating the property power supply and testing equipment on battery power.
Nice job, made a similar one a few years back to suppress the noise from the dish-washer in our house, when the wife turned the blasted thing on, its was making more noise than an 'over the horizon radar' on HF.....mains filter solved the problem.
Subscribed, as i am looking forward to see just how many 'thumbs up' you can squeeze into the next 15 minute video !! 👍👍👍👍👍👍👍👍👍
👍🏼👍🏼👍🏼 😂🤣😂
No doubt someone else has said this but here goes. Red, Blue, Yellow crimp terminals are not for colour coding your connections, they are for different gauge wires.
Yes. I don’t know if that’s universal and I suppose it’s possible that it’s not always, but on these it sure looks to be the case. I paused and zoomed in. maybe that’s why he had trouble crimping.
Seems like a useful project though. Maybe one day I’ll make one…
You are indeed correct… although given how cheap and poor quality these were it made little difference. I have since replaced them with good (all the same colour/size) quality connections.
@@M7EUP .Thank you for sharing,good job done.
Correct crimping tools, will have jaw slots which are colour coded to correspond with the coloured terminals.
Perhaps you could have finished off with a demo with it in and out of line in short time span.
73 de ZL1PO
I built one during lockdown and furlough. It ended up going into a much larger box because of the mains filter was a lot bigger than Ian specified. So I put a 4 gang socket unit directly on the front along with a 30mA trip on the outputs. The rest of the house is on wired fuses and a ""master on/off switch. Incorporated into the unit I added a voltage/current monitor module. Works a treat, noise level dropped by several S points and the addition of 1:1 current baluns at the HF antenna feed and in the shack have brought the noise right down to S1 or 2 depending on band. By the way the crimp connectors are colour coded by wire size. For the wire inside the box you need the blue ones and for the input and out put you need the red ones. The earth might need a yellow for both wires. Use some hot snot or neutral cure silicon sealant to glue down the ferrites.
Glad it worked for you too 👍🏼
Thanks for the video. I would recommend using ferrules at the connector block.
👍🏼
Glad you got the large faht cleared out. ☺️
Thanks for this video. Very interesting.
You’re welcome. On both counts.
Great video on an often overlooked subject. I'll be looking into this and trying it out. I also have a Yaesu FT-450D on and EFHW wire and it seems that more often than not, the noise floor is rather high, especially on 40 and 20 meters. Oh, as a side note, I didn't have any difficulty distinguishing between ferrite and Fair-Rite in your narrative, and I'm not British.😂
Thanks Howie,
It’s cause a bit of a stir has the old Ferrite / Fair-Rite for sure
Check that you actually have a mains borne RFI issue before spending any money doing this.
Very well-described and informative video, well done.
Many thanks.
"Two fools, one thought!" - did the same with my setup.
Was able to receive 100mW packets from our TRSI-2 satellite on 500km orbit with a small omnidirectional antenna.
No switching regulators of course, clean copper&iron transformer, linear regulator etc. I was living in a valley in the countryside: spectrum clean as a monk's concience! A good LNA and a sharp bandpass filter squeezed the noise down even further.
Noise is the biggest issue for most people and this is just a solution to a tiny part of it.
A better way to mount everything in that box is to cut a piece of 2 or 3mm plastic sheet to fill the bottom of the box, this can be screwed to the rows of mounts provided in the bottom of the box using self tapping screws, then either (for the filter) screw it to that sheet, and for most of the rest, drill holes for cable ties. This way everything is tied in place without any holes in the bottom of the box.
Good idea 👍🏼
Thanks for your video. I'm not into HAM radio but it can be useful for my lab or problematic (not very well filtered) HiFi. One thing: You screwed the stranded mains wire directly into you screw connectorblock ("Lüsterklemme" as they are called here). You should (must) use ferrule to prevent the screws from damaging the strands. Furthermore these connector blocks often are rated only for 8A or 10A, so you need to replace the fuse in you plug. The other solution would be to use elevator clamps or other types were the screw isn't screwed onto the wire directly. Or use WAGO clamps, 221 or 222 series.
Thank you for the comment.
As I’m sure you’ll appreciated, when making videos like this it’s often a learning curve and often difficult to capture and edit the entire process.
I should really do a “follow up” video to this as, like you say, it needed a few tweaks once proof of concept was established.
I have replaced the connector block with ferrules and have also replaced the push connectors with more appropriate and better quality ones which have been soldered and heat shrunk.
Thanks for the info , Mouser links are down so i just ordered the whole lot via Ebay , still worked out about the same price .
Thanks
Excellent. Enjoy the build
I subscribed solely because of your fart honesty
Honestly I would have left it in the edit if it weren’t for the fact I may have got a strike on the channel !
Thanks for the sub 👍🏼👍🏼👍🏼
@@M7EUP I've never heard of a strike for a fart. Strikes are mostly for copyright and endangerment other than nudity.
Cool demo. Would have liked to see you unplug it from the filter and direct into the wall afterwards though just to show back to back readings.... For me, my RFI issues on certain bands come and go over periods of time...
Sadly most RFI issues are received via the antenna and not the mains which is why I always suggest running on battery with the power off to ensure that mains RFI is the cause.
If external RFI is an issue then have look at this ruclips.net/video/lP3RiX2KkRQ/видео.htmlsi=BjPFAqq-dX8568On
They are colour coded because they use different size of wire.
Might be a good thing to place the ferite cores 90 degrees off of each other. Don't know if it applies to noise filtering. But at least for RF it does.
But a great project.
There is some video where they say do not connect earth to your devices but make your own. Isloating.
A lot of this is covered in previous comments and replies but thanks for taking the time to add yours.
Appreciated.
When laying out a case, use blue painters tape around the outside, then you can mark up as much as you want with a fine pencil, drill / cut as required, then peel to leave a defect free surface.
Good tip 👍🏼
@@M7EUP If you only mark out where needed, the 20mm hole that is drilled removes the scribed layout. 😉
Excellent, going to do the battery test.
🤞
Past the filter, you have a very long extention cable that would pickup noise. If one would slide metal braid over the cable, i would think you could have a little bit more protection.
Oh that’s already shortened to 1m… was just easier to film that’s all.
Darn it Matt, you’re going to make me spend some money and build one of these now!
Apologies.
If you do, stick to the instructions in respect to parts, number of turns etc. I’ve seen so many people try this and add extra turns or get alternative Fair-rites etc and it just doesn’t work.
I can tell from the tone of many of the comments that you've attracted some genuine HAM radio people to this video 😉Nice work. 73
Thank you
Excellent, thank you. Some of the comments though - wow !
Thanks for your positivity. Appreciate it
in-between the mains filter and the 6 gang extension i also wound a couple of type 43 and type 61 240 ferrites probably overkill but had a couple spare.
“Possibly overkill” 😂
The protective conductor should definitely not be twisted, only the phase and neutral conductors, and with multiple strands, for example, 8 strands of 0.25 square mm each. Here's how: take two strands of phase and neutral conductors, twist them together counterclockwise, then take another pair and twist them clockwise, alternating between counterclockwise and clockwise. This must remain symmetric throughout. Afterward, you should have four strands made up of phase and neutral. Twist two of these four strands clockwise and the other two counterclockwise. This ensures symmetry. As shown in the video, you can simply get double the number of ferrite cores. The protective conductor should be separately filtered using a ferrite ring, placed as close as possible to the filter's input. There’s also another reason why the protective conductor should not be twisted together with the others: doing so induces voltage on the protective conductor, which can lead to interference. The filter itself already induces voltages on the protective conductor since capacitors in the filter are connected to it.
Additionally, every device connected in any way to the radio equipment must pass through the filter; otherwise, ground loops will occur. This includes computers or any other peripherals, as they can introduce differential voltage issues.
Thank you for your input. As you’ll see from the other comments it’s a very debatable little project and something that can always be improved upon.
I built the filter to the original design but I’m sure that it can be developed further.
nice work, yes they do work well, dint do a thing for my shack, as it's the same on battery still there even with both and mine mains off, so my problem is airborne. although you mentioned something your video that may shed some light why mine didn't work, I never broke wind and left for 10 minutes lol.
Hope you get yours sorted.
I wonder how a filter system like this would work for audio, or test instruments, such as an oscilloscope. I get a lot of interference, when trying to trace small signals, where I need a lot of channel gain.
I’m. It nearly qualified enough to answer that question but would say that ie would be entirely dependant on where the interference was coming from.
The problem with this approach is that any piece of equipment connected, which is also connected to earth ground (antenna ground) bypasses this device. I built this and while it helped, as soon as the radio earth ground is connected the noise returns.
Interesting point, something I’ll look into.
Easy = don't connect a ground to the radio
I can't earth my radio anyway, my shack is on the second floor, any earth wire would act as an antenna, I have ferrites on my equipment and have a fairly low noise floor across the bands.
An earth ground can greatly help with reception and SWR issues though. @@M0RMY
I built a couple of these a few years ago, extremely effective, fwiw I don't have the join at the connector block. the output cable going all the way through the ferrites. A similar reduction in noise to yours on 40m in particular. I used similar ferrites on the phone line (VDSL) and the LNB cables to the satellite dish. Just to address a few comments, the box SHOULD NOT be metallic, and a UPS will not generally help with common mode RF. 73
Thank you for this 👍🏼
The colour code of the terminal is for the wire size and not for the function of the wire.
👍🏼
Superglue in the eye, yep. Also be careful if using a heatgun as superglue fumes sting as well.
Yep. That too
Thx for sharing! 👍
You’re welcome
When I connect my radio to a dummy load (cantenna style), the noise floor goes to zero. So it seems to me that a line filter won't help in my case.
I would agree.
Nice video Matt thanks for sharing ,i was wondering does it matter if there are more turns on the farites ?
Good question.
Essentially in a lower frequency range, an increased number of turns can provide a greater reduction. However, as the frequency increases, the performance of a higher number of turns can be worse than a lower number of turns.
It’s a bit of a balancing act, but for the purposes of HF and VHF radio in relation to mains borne RFI the original author will have calculated to optimum performance.
This is why I also state to only use the parts listed, from the cores themselves to the gauge of wire
Hope this helps.
Yes I’m building one I’ve ordered all the parts from your link and also why are the wires twisted 😊
@@drmisfit 1) twisting wires will reduce the magnetic flux between them and so the EMF pickup, this is why low-level signal cables should use twisted pairs
2) with controlled twisting we can have well defined inductance/capacitance per unit length, making a transmission line with a well defined characteristic impedance.
Hi Matt thanks for the clarification hopefully catch you on the air sometime 73’s
@@drmisfit 73 👍🏼
Excellent video! I do have S9 noise on most bands, most of the time. Only problem for me will be how to get hold of the parts in this part of the globe! 73 Jon, VU2JO
Just make sure you clearly establish that it is Mains RFI by turning off the power and running on battery.
@@M7EUP That advice has been given to me by all my local Elmers as well. But I have not invested in a battery for the shack yet. Home inverter has couple of large batteries. Unfortunately I had not planned that to be near my shack when I built the house! 73
@ it’s a worthwhile investment, even if just for testing purposes.
You don’t want to be spending a load of money building a filter if all your noise turns out to be a dodgy transformer in a street lamp outside.
@@M7EUP You are absolutely right. 73
Just so you can complete the test why don't you borrow a battery.
It's alot of money for a one off test.
It doesn't have to be lithium a reasonable ah car battery will do.
Save your money for good quality coax......
1st .. as always sir very informative content :) your subscriber from philippines , 73
Congrats… you win First Comment 🥇
@@M7EUP sir can do ah power output test on quansheng uv 5r plus? because im planning to buy one :)
@@sensei2pointzero572 ruclips.net/video/XMhlmeMBXfI/видео.htmlsi=WCwWAKJ8YGzOGox0
@@M7EUP sir i mean QUANSHENG UV 5R PLUS.. 😁 not baofeng 5rh/5rm
Great video
Thank you
you should put MOVs in the circuit as well, the main reason why amplifiers die has to do with power surges
Thanks for the comment, most modern power strips contain MOV’s ( Metal oxide varistors ) to some extent to regulate power surges.
However, in HAM radio application the transceiver is not usually directly connected to the mains power supply. It is fed 13.8V DC with a power supply unit, thus adding another level of protection.
You are using incorrect size crimps. You do realise the colours denote different size wire.
It has been mentioned…
A lot!
@@M7EUP Time to do something about it then! Using crimps that are the wrong size can have pretty dramatic implications for safety and all that, what-a-ma-with the sparks and flying leads and such!
So it is basicly two rf chokes that converts two ranges of frequencies into heat? If you have a variety of ferite cores stripped from power supplies or inverters, can you not just measure the inductance to calculate the approx frequencies ranges that will be filtered?
The idea is to cover the frequencies that are most commonly used in HF and VHF and help to keep those “clean”. What you suggest is valid but specific to the interference for each individual.
If you have an idea of what your interference is caused by in terms of amplitude and frequency, then that's certainly a valid choice of method.
Don't forget about common mode filtering if you're working with noise induced on your power lines when they were running parallel. The twisting can help with that, but is generally not a great way to do it unless you're working with signal level wires.
When choosing your cores, make sure you consider more than just the final inductance you're aiming for. The final inductance of your choke will depend on the wire size you use, the amount of insulation between the core and the wire strands, the size of the core, the exact permeability of that core (ferrite vs moly powder comp vs moly film composite etcetera), and how many turns. Since the wire insulation distances the wire's conductor from the inductor's core, you can see why we use magnet (lacquered) wire on magnetics.
Any inductor, whether it be from a clamp on ferrite core or a tightly controlled winding benefits from even spacing around the core. Don't cross the direction of your wires, as that'll cause more harm than good. Don't try and combine your CMC and your low pass filter chokes!
A little portable AM/SW radio works to locate your RF noise makers, then move all that crap into the _basement_ and then you'll have a LOW "noise floor"!😋
😂😂😂
I would have held the toroids in place with a bit of hot glue. Also if using a screw connector block, I would have crimped ferrules on the ends of the stranded wires. Other than that, great job. 👍 👍 😁
You’re absolutely right John and that’s exactly what I did before permanently installing it in the shack.
Great advice. Always happy playing with the old hot glue.
@@M7EUP I prefer the Wago connectors over screw terminals, and you can get in-line ones as well. They're good for high loads as well.
I'm a returning operator who needs to find the time to get my shed converted into a shack, as my wife does not want the equipment in our house. Because of that, I'm only operating on 2m & 70cm at the moment, but I may see you on HF sometime in the future. All the best, G4MLZ.
@@johnharrison373 won’t be long until you have a little HF set in there and a long wire running down the garden mate
@@M7EUP 👍
What is the electrical purpose of twisting the wires together? Thank you for this video.
That’s a great question.
If you can visualise any interference travelling up one wire and back down the other in opposite directions like ripples heading towards each other in a pond, when they meet they stand a chance of cancelling each other out.
Twisting the wires increases that chance.
That said, anecdotally people have built these without twisting the wires and seen little difference in performance.
However I would always give myself the best chance of reducing any RF so I add the twists.
“Common mode rejection”
Would it be advisable to avoid using extension socket leads with a neon light installed in them
That’s a valid point but makes not discernible difference on the extension I purchased. Good comment though.
Can you give me the part number for the box with the clear lid you used? I really like the it. Great video. Thanks
I honestly don’t have it to hand but I got it from cpc.farnell and if you search “IP65 enclosure clear” you’ll done one of the right dimensions.
@@M7EUP Is it the 190 x 140mm enclosure?
Excellent device. Are you really sure that on the fairrite website that is the correct ferrite despite the wrong picture ? I don't want to end up with the wrong one !
Yes it is definitely the right one. Even the original PDF says “ignore the picture” 😂
Excellent.
Thanks
Filters and HAM are outside of my knowledge base. Meaning, I do not have the ability to design the Ferrite filters for USA/120VAC/60Hz/Broad bandwidth general use EE hobby lab frequencies. However, I have a spare can filter. I would think that just adding it on the power plug strip would help somewhat = better than nothing. Thoughts/suggestions? Thanks. Cheers. Hmm, now that I think of it, the filter may be limited to 6A. I will need to check that. The wall socket is up to 15A. Depending on the DUT and the test equipment being used, I could be pushing 15A.
I would say it entirely depends on your need/application
The filter (silver box) is rated up to 250vAC ✅ filters 50 & 60Hz ✅
The cores and number of windings is selected for RFi elimination on the Amateur radio bands… 1.8 to 10 MHz and 14 to 50 MHz.
You mention you use filters in antenna feedpoint and in the shack. What filters are they ? 73
I have a 1:1 choke in the shack just as the coax enters the radio. This stops any common mode current that may be on the sheiks of the coax.
Always double thumbs up
👍🏼👍🏼😂
Very nice
Thanks
I have power line noise but not via the mains. Is this because the transformers isolate the noise and only the antenna and possibly coax are receiving direct from the powerlines but not from the mains power? I've tried on a battery, no difference. I tried putting the noise canceller aux antenna close to a mains lead but it doesn't help. best result was a large loop of wire in the gdn as the aux ant for the canceller. driving around I get loud noise around those smaller power-lines whenever I pass them. There is a hydro electric power station around 3 or 4 km away, sometimes the cables are buried below ground for some sections. I don't think I will get any help from the electric company in France.
It’s worth trying to report the RFI to the radio regulator. I’m not sure how it works in France but in the UK OFCOM will actually investigate and order companies to improve. It’s important for not just Amateur Radio operators but for all types of communication including emergency services.
Give it a try.
One night, the noise suddenly became worse than ever. Turns out that the smart meter was going haywire.
Wow that’s good to know. Hope it’s all sorted now.
@@M7EUP I called the power company about getting estimated bills. They came and replaced the meter. The noise disappeared and I got regular bills again.
Smart meters are bastards of things on a number of levels, including RFI.
would this be worth building it for use with studio recording equipment?
Certainly the first component, the silver box mains filter, would help with any mains borne noise… however the torriod/ferrite cores are made to eliminate noise on frequencies used by amateur radio operators so whether these would be a benefit is not something I could answer, as I have no experience in studio recording.
Absolutely..the pops crackles and whines are coming fom switches and electric motors
Hi mate,
that's a great video you posted there, thanks for your efforts, i have a different problem over here, i seem to be causing electromagnetic interference in the power lines of my house and can hear myself coming in through the speakers of my amplifier for my entertainment unit and i seem to be knocking out the network cameras every time i tx, would this device help with this ? I put the interference down to bad filtering n cheap Chinese products as it only occurs in a could of appliances.
In all honesty a mains filter is not the place to start. If you are causing EMC like that the you really need to get to the bottom of why. It would be helpful to know your set up to help work the problem. Radio, PsU, coax, antenna, antenna location etc etc
@@M7EUP Thanks for getting back to me, I am running a SE HP360 XP broadband antenna on a 9 meter pole, running into a MFJ 986 roller inductor tuner, a president p400 27mhz cb and president hr2510 radio., running rg213 coax everywhere . I intend to try grounding the MFJ tuner this weekend with an independent ground stake, i also yesterday grounded the roofing iron and seen a notiaible difference so will see how grounding the tuner and station goes. If the filters you describe work could be handy for handing out to people I am interfering with, had one such complaint a while ago and replacing his clock radio fixed the problem so i pout it down to poor filtering in the device. havent had any complaints since then.
I think perhaps a mains filter would be an expensive way to go in this instance. Maybe have a box of torroid rings ready and wrap the power leads of affected items through them.
@@M7EUP have tried that on the network cables of the surveillance box already for the cameras, that did not fix the issue, the power cables for the mains being high voltage, i have been advised not to do this to mains cables as it may cause heating from the inductance created. So just asking again, would you mains filter help the situation and would grounding my tuner and my station help also ?
@@thearchitect4726 it’s a tricky question to answer. In your initial question you stated that you were hearing your transmissions through audio equipment which would lead me to suspect that the interference was being captured via a receiver rather than the mains power supply. Similarly if you’re getting issues with broadband etc.
The only way of knowing is isolate your property power supply and run your radio and affected equipment on battery power. If the problem is still present it’s more likely to be an issue with the location of your feed line and antenna.
You could certainly try grounding all of your equipment although this is not a “cure all” for many issues.
As an experiment try transmitting with the radio outside of the property on battery power a with a shorter length of coax that is away from the property.
Can you filter a whole 15a circuit with this
Maximum current would be 13amp at which point you blow the fuse in the plug.
How'd you determine what number of twists to use per foor? Why did you include the PE/ground wire in the twisted pairs?
All my knowledge of circuit design (which is mostly limited to high performance amplifiers) tells me one should not twist mains wire for normal use, and if one *does* twist it to reduce the coupled noise, then it should be just the L/N wires and no more than a couple of twists per foot, say four to five.
I'm eager to know what your number of twists per foot was based on, or the reason for including the PE/ground wire in the twisted pair. Or even why you're twisting them at all.
The answer isn’t straightforward. Where low frequency is concerned (audio and below) the theory of the twisted pair effectively creates a situation where noise on one wire is cancelled out by noise on the other. It also rejects interference from outside as both wires cancel out any incoming fields - similar to common mode current on transmission lines. The twisting couples the fields around each conductor in a way that reduces flux leakage. You could look at it like a rudimentary form of shielding where braided coax cannot be used. Most analogue telephone systems used twisted pairs, and in old valve equipment, the cathode heater wires (which were low voltage AC) would be twisted to reduce radiated hum into other parts of the DC circuit. Where you’re looking to suppress RF then twisting the conductors should reduce any RF from coupling into other conductors and reduce crosstalk. So I would assume that the design of the filter was aiming to do something similar, by twisting the noisy mains conductors and reducing the possibility of any noise bypassing the choke and coupling into the clean side.
I’m not aware of a formula for determining the degree of twist but from past observation it’s around 6 twists per inch…
Or in other words I followed the instructions exactly as they were written by the original author.
As for the emergency earth there is an argument to say that this not should pass through the ferrites and have its own filter. However I again refer back to the original plans.
A very good way to stop interference is getting an uninterruptible power supply as most of the time these are charging batteries and powering off of them in such a way that it’s being inverted again to a pure sideways with no interference I would highly recommend using singles which are single inch related cables or try rated singles instead of stripping back flex but it depends on where you get your supplies from as many eBay sellers will sell these cheaper than the roller flex costs. There may be an issue with how tight the windings are round the ferrite because it would count as group so the current rating may need to be adjusted but I think it’s fine based on the size you have used (you probably looked at all of these things, but just didn’t mention it on the video
Thanks for your input and knowledge.
Most, if not all uninterruptible power supplies do not work as you describe. They charge a battery and keep it charged. The mains output is just fed through from the mains input through a relay. If power fails, the square-wave (of modified square wave at best) inverter kicks in and the relay changes over to the inverter. So, there will be absolutely no clean power from these units.
@@meindertsprang7491 however you need to get ones rated for IT equipment and sensitive service stuff. They are amazing they have really pure power. They’re quite expensive new but they pop up on eBay all the time data centres replaced regularly so they don’t fail they use a transformer based design so a square wave would not drive the transformer properly
Great video, but I think you are making a mistake with crimping choice! Colors on plastic isolated crimp connectors are to match the wire gauge and NOT the wire insulation colors!
Thanks for the comment but I’ve had dozens of people pointing that out already. 👍🏼😂
nice work ..
Thank you.
What about all noise from those solar cell production unite that everywhere? Do this will help then?
If that noise is being picked up via the mains supply then yes, you should see an improvement, however, as I say, test your radio with a battery and the mains power completely off in the house. If the noise goes then this will help.
@@M7EUP More specifically, common mode chokes only work for common mode noise, which means the phase and amplitude needs to be the same on both N and L. That generally does not apply to or is not the case for noise generated by equipment directly hooked up to the power lines, as they either have a CMC on them already as a required measure, or do not produce truly common mode noise.
Common mode noise is primarily present when that interference is *induced* on those wires simultaneously and when they run in the same direction of current flow. The common mode interference would hence be filtered out by a common mode choke where one of the lines runs 180 degrees out of phase -- meaning, the current flows in the opposite physical (N-E-S-W) direction from previously. That would essentially mean having one of the conductors enter the two-wire inductor from the opposite end, as to invert phase. In reality, most CMC's are built in a way where you can wire them L/N in and L/N out without needing to worry about it. 🙂
Feel free to ignore the latter explanation if this sounds exactly opposite of the actual way it should be -- that means you're already thinking about magnetics, and this physical world explanation doesn't apply to you.
Nice but it will be better to add a little drop of hot glue to the filter and ferrite to not move around.
Yes and I did… sadly when making videos like this you can’t include every tweak and fine adjustment or they would be an hour long.
@@M7EUP Ok i understand, anyway nice and useful video.
Why did you not solder the connectors to the leads. Nice job.
There’s an argument that says soldering a crimp connection only serves to create a hard and brittle break point. I suppose it personal preference.
Yes, that sounds interesting. That would apply I think if the leads were in an area where there is constant movement or vibration.
1:52 Ah the famous UK ring circuit 😂
Yes… the “ring main”
@@M7EUPring mains are in your street, a ring final circuit is in your house.
So there is/are no component(s) in this unit to deal with
Correct. You would need to add a third fair-rite for sub 1MHz… I couldn’t tell you the material or number of windings right now but it’s fairly easy to look up.
@@M7EUP Thanks for the reply and the video.
Good grief ! Some of these comments lol. I tried my radios (yes I have multiple ones all bought second hand but my 450D I love best) on batteries and still have a high noise floor. Unfortunately behind my shack is a new housing estate and I suspect that the noise is from there. Last couple of years lots of solar has been appearing as well which has made it a lot worse. Ah well I will have to go mobile or move. 73 M7BLC
The 450D was my first radio and absolutely loved it
Interesting that the mains filter does not actually filter the earth, as they are connected directly via the chassis of the mains filter, it appears. So the mains
earth filtering is non-existant it seems. Odd to bother mains filtering the live and neutral then allow it to be in contact with the unfiltered earth in the torroid wrappings, plus the torroid windings need separation between the start and end of the windings...otherwise you just undid the point of the windings, because they are touching each other.
One other thing on a different point ....How do you intend providing an RF earth in your shack...out of curiosity? I ask as some years ago when Ian released his RSGB videos, myself and others pointed out the error of his ways in doing this, his repply to me was to consult an electrician, as he wasn't one, with regard to RF earthing dispite having a viseo about it advising people. Myself and another electrician who were amateur radio operators exchanged a few emails with him regarding his very subject, and his mains filter, plus TNS, TNCS ans TT earthing systems, and the dangers therein. Still if it works.....???? Forget the safety I guess???
I Was wondering the same about NOT flitering the earth.
I am nowhere near qualified to give you a scientific answer to this but on a basic level…
The mains filter filters current, up to 240v, 60/50 Hertz. The earth wire doesn’t carry current so does not get filtered at this stage. It is simply attached to the case of current bearing filter for safety.
There is no break in continuity of the earth wire from plug to socket.
The earth wire DOES pass through both Fair-rite cores which deal with stray RFI.
Finally, RF-Earth is an entirely separate issue and is dealt with in the normal ways, this eliminator has nothing to do with RF-Earth.
See reply to original post
The Tacima CS929 block is a budget filter block, however the filter board has an earth-line choke amongst other things if you want to see if it brings down mains noise any further.
@@M7EUP I understand that RF earth is a totally different point but was curious exactly what you did for your shack,,,,,and just mentioned Ian's view on it for completeness of RF in the shack. Good informative video though on a subject that causes some people difficulty...and I am glad this worked for you...even with an unfiltered mains earth.
At least the earth has a choked effect at the frequencies mentioned in your video and that will help and some people put a few clip on ferrites on the mains side of this filter near the plug and actual filter too, as all exposed cabling is liable to RF pick up especially if the cable is of a resonant length or multiply resonant lengths on certain frequencies....
The subject is vast and once you succede in filtering the mains incomming, you then have the issue of self generated RF within the shack and then antenna feedline RF pick up, passing stray RF via the coax feedline braid into your equipment cases as they are connected to the coax plug directly and are negatively earthed via any transformers that power the radio equipment thus the RF enters your filter backwards if you like.........and ...on....and....on we go....ha....
Good video though and will help most folks out.
Enjoyed it....and it gets people chatting....about it....especially if it is affecting their hobby and other household equipment...
This doesn't include RF earthing coax outside of your shack with a ground/earth rod as now you will introduce a potential voltage difference into your shack if a mains electric fault developes within your home..... ha...ha.... crazy this hobby.....
My next reply will be made available in hardback from most good (or bad) book shops...ha.........Cheers.
I have the same pocket knife as you where using to cut the flex with does it say pakistan steel ?
I have no idea. That’s been in my possession since I was a scout over 35 years ago.
I’d have to have a look.
Nice video! However, I think the link to "Large type 43 Fair-rite" may be wrong.
No it’s not. Ignore the picture it’s the correct one.
Is there anything in particular that would be causing interference on 160 & 80, but not 40, 20, and 10?
First thing to check is your own power supply and household electrical me by switching off the power at the fused box and running on battery.
If it’s in the home you then need to narrow it down to a specific item. By turning on circuits one at a time.
I’ve heard of laptop chargers causing interference on 160 and 80 but it might not even be in your own home.
I compare with a battery. Then I can see if there is any.
Correct
If I hold the frame on my G90 the noise reduces, perhaps the frame needs earthed?
Actually no. This phenomenon is common mode probably from the antenna shield.
Could be a bad connection or a significant amount of RFI externally.
What antenna are you using.
Thinks to check:
1: SWR (is there a problem with the antenna)
2: try a different antenna
3: it’s common practice to add a common mode choke balun at the shack end of your coax before it goes into the radio.
@@M7EUP The antenna is a glass fibre moonraker, the power supply is near to the transceiver and was only around 25 pound new for a CB . I did wonder about upgrading it for a low noise type .
From the very north of England I have been into Russia, Germany, Hungary, France etc on 20 watts.
@@union310 I've got the same radio. Make sure the RF gain isn't set high ( that just amps noise!) and add a common mode choke right at the radio. Any coax braid between the radio and antenna will pick up all kinds of stray RF noise like an additional "random" antenna element without using a choke. The channel "The Smokin Ape" has tons of common mode choke videos and tests, really easy to make.
You'll want to use a mix type "31" toroid core like a FT240-31 toroid ferrite core if you can, as the 31 mix works better for the G90's full band range vs say the more common FT240-40 type 40 mix which falls short in the 40m and 10m bands. That and 1-2m of some cheaper coax jumper like RG-58 or even RG-142.
@@macgyver5108 Brilliant thank you very much for taking the time to help me
@@union310 73
hi matt did you use two & half meteres ?
No I had quite a bit left over.
I suppose the amount of turns are the most important , I’m just waiting on the fairrites to arrive, I had some Perspex left over I mounted the filter to that with some pcb chassis mounts and secured the Perspex to the box
@@drmisfit Hiya .. Yes that was my main Q .. Is the amount of turns important and if so what frequencies do you think it effects?
@@JediBuddhisthi ya if you gave a look on RUclips there is a video which shows the best bands this works on
Isolation transformers are great
Yup
Any particular reason for building a filter and then popping it in a plastic case which will propagate magnetic fields beyond the case dimensions? Might a grounded metal case reduce magnetic fields and improve the filter’s overall performance?
It’s a good question but you are more likely to cause more issues with a metal case in terms of the RF coupling to the case itself.
@@M7EUP That seems counterintuitive, but I'm more DC (audio) than RF, so I'm not entirely surprised that weird stuff(TM) might happen... On the other hand, though, RF stuff is often in cans for exactly this reason... 🤔
Do the commercially made filtered 6way sockets work??
Yes. Just always be aware of your current draw and don’t exceed
Hey, would this mod benefit HIFI amplifiers?
That would entirely depend on the type of interference you want to eliminate and its frequency. What sort of issue are you trying to fix?
bzzzzzzz bzzzzzz
The filter cost me more money to build than my radio did…
Ahhh but did it work?
Its not on the power source.. get yourself a magnetic loop or LOG and say goodbye the noise.
Clearly you didn’t watch the video.
The Mains filter is for Mains born noise. The clue is in the title and the instruction to “test on battery power with mains power turned off to first establish the source is FROM THE MAINS SUPPLY”
Would an isolation transformer work?
For the purposes of Amateur Radio (Ham Radio) we do use isolation transformer for a number of things like impedance matching and choking. You’ll hear us using terminology like 4:1, 9:1, 49:1 etc or 1:1 in the case of an in-line choke. But these tend to be on the antenna side of the radio and not the power side.
Essentially the build in the video is aimed at removing unwanted RFi from the power supply and targets specific frequencies that affect us.
Are you pronouncing ferrite oddly, or are you always using the name of a particular manufacturer which I seem to remember call themselves fairite?
I’m used to the brand “fair-rite” which apparently annoys a lot of people 😂
NOISE!
I appreciate the comment but feel like I need a little more context?
getta better crimp by leaving the wire strands straight rather than twisting them. (better than my spelling.)
Might be a hard habit to break. *lights cigarette*
Good tip.
Another tip, don’t buy the worlds worst connectors from Chinese drop shipping sites.
@@M7EUP I bought some cheap ferrules and a cheap ferrule crimping tool. The ferrules are fine but the crimping tool does leave a slight star shape profile instead of square. It still passes the pull test though so it's just acceptable for hobbying.
@@M7EUP The colours designate size of cable NOT earth, neutral, live . Probably why you had issues with crimping them. Although I don't recommend cheap connectors either.
@@militaryrig yes I am aware thank you.
@@M7EUP ah yes, I first watched it when it was uploaded and had not seen other comments. Anyway I am going to attempt to build one myself :)
Why a plastic box, mild steel would be far better.
Ok… why? I’m interested to know your scientific reasoning
@@M7EUP I guess he's alluding to better shielding. However, it does the job as it is.
Is mains electricity is going through a metal box can work if it’s earth but a plastic box is safer because it will be classed to double insulated so it’s just means if there is an earth fault you can’t get a shock if something goes wrong from the enclosure
Esse é o novo radioamadorismo, compra tudo pronto, não sabe fazer um simples filtro de rede.
I’m not sure I understand what point you are trying to make.
I have exact same radio since 2018 :P
The 450D is a classic 👍🏼
@@M7EUP really? I was told it's not worth buying but I did and have more than 30K logs hahahaha
Tidy job
Thanks Stu
I built one of these about 5 years ago. It makes absolutely NO difference to the noise floor. Shutting down the entire house supply and using a battery makes no difference either.
Unfortunately if shutting down the house supply made no difference then by definition the “noise” isn’t from your mains supply and this filter won’t work for you.
'Ferrite", other than that, great video. Subbed.
Yeah I can’t get the brand name “fair-rite” out of my head, sorry about that 😂
@@M7EUP good video all the same. Nice to see something that's achievable as opposed to someone going out and dropping £500 on a random antenna and mounting system for a 20 minute video.
OMG ! =)) at 9:43
You’re welcome.
Fairite I think you mean ferrite!!
Omg that’s so 2024!
Or you could stick a ferret in there if you really wanted to have some fun!!! 😉
Just to think I used to moan like h ell in the 1960's up in the Chilterns about 16khz harmonics from TV's.
😂 I used to get into trouble using the side banded CB in my bedroom as a kid and making all the neighbours tv’s go fuzzy
I remember making hundreds of braid-breakers to fit right at the back of TV sets to reduce the timebase harmonics radiating form the TV antenna feeder. Bonus was it formed a high-pass filter. I think I used a design from TT or an RSGB book? Long time ago now.
Gave them to neighbours up and down the street and it made a huge difference on the lower bands.
Yuck. A company used the name "Fair-Right" to confuse consumers looking for Ferrite cores.
Ok 🤷
FAIR-RITE
It would have been much much better to show, at the very end, an actual comparison "with vs without" a few seconds apart.
Thanks for your input 👍🏼
Are you aware that in Australia the thumbs up sign is an insult relating it to 'stick it up your arse"? Had buil5 a similar device in sth3 states some 35 years ago. I would have used here in the EU but the COR COM filter is rated for only 120 volts 60Hz. Time to order these parts and build another filter for use in Europe. Also have issues with corona discharge from a 7kilovolt to 220-380 volt three base pole mounted transformer. We are only 1/2 mile from the ocean here and that salt builds up on the insulators. On damp mornings the noise floor is unbearable!
Never knew that about the thumbs up!
Costal substations suffer massively with salt build up too.
The Australian/Greek folks take it as an offense. ...and it's all in the action.
Never heard others take it so.
I’m in AU. Thumbs up emoji is fine. It’s a middle finger thing that means “up yours”
The aussie stick it up your arse thumbs up thing is really only a problem if you go wagging that thumbs-up vertically. I'm sure no sane aussie's over here getting insulted by a kindhearted "Great job!" with a thumbs-up 😀
@@BTW... I am Greek and living in Greece and it’s been only in the last ten years that the middle finger has gained as a vulgar sign. For many decades the Mouzoma aka the palm of five open fingers in towards one face was the insult gesture of choice. About eight years ago the government here passed a law prohibiting the use of that gesture by drivers on the road and supposedly it’s an offense that carrys a fine.
Shack farts are the worst... and malcolm is cute
😂
Do you mean terminal block?
🤷
Lol all the yt experts are commenting on your video mate......only a radio boffin invented it so yt commentors shut the front door up wingeing f#@×...
What size are the oval cores please mate I need to build one as farmfoods fans proper kill me with rfi..excellent video and very educational
Some people just need to have their say, welcome to RUclips.
All the individual items are listed with links in the description.
If you go to the link for the oval cores you’ll be taken to the mouser website. Click on the Data Sheet link from there for the full specification.
@M7EUP excellent and thanks so much
You should have used neutrik powercon
Ok…. Why?
@@M7EUP well the box would then be portable and qick connect, its litrally a twist lock socket and plug that wont arc on connection
Fart😂
Always funny. 🤣
It's 'ferrite' not 'fair right'. Fair-Rite is just a brand.
I used the brand “Fair-rite”
@@M7EUP I appreciate that, it just sounded like you were using incorrect terminology. That's all. Was there any particular reason to use that brand over another?
@@DelticEngine yes, because as GM3SEK says in the presentation and the documentation it is vital to use only the specified parts and part numbers listed. Alternatives will have different results.
It’s really important for people to follow the instructions to the letter and that includes actually establishing the main borne RFI is actually an issue by isolating the property power supply and testing equipment on battery power.
@@M7EUP Nonsense. Ferrite is ferrite and as long as the electromagnetic properties are the same it doesn't matter.
@@DelticEngine unless it's FarLeft or FarWoke
:O)
im surprised a licensed opperator doesnt use the correct name of ferrite, you keep calling them fair-rites which is a brand name...
I think you’re only the 409th person to mention this.
@@M7EUP Geez.. Who gives a shit what you call them.. Tell them to sod off.
Be very careful never to use a kleenex, or a hoover.
@@DXCommanderHQ😂
@@James_Bowie😂
Ferrite. Not fair rites
A simple google of “Fair-rite” may enlighten you sir.
But thank you for your well intentioned if somewhat hasty comment.
@@M7EUP Fair- enuff.
Never heard of that company before!
@@mikhan5191 - Fair-Rite has been around for a long time. Company I was at used some of their products in the 1980s