Reddit mentions: The best electronic ferrites

An alternative possibility to rogue radio stations and smart meters along the same mien - but a bit harder to find out - you could live near an amateur radio operator.

Amateur packet radio can sound similar to the noises linked above as it's a digital data communication.

Plus, if you are based in the US, amateurs are allowed to transmit at up to 1500 watts of power, (more power than your average microwave oven) so it could make your speakers go crazy at close range without them even being turned on.

The downside to your situation, is that as long as the local ham is operating legally, there isn't much you can do about it. Your speakers would be type-certified as following FCC Part 15 rules while their amateur setup follows FCC part 97 rules - your speakers legally have to receive the interference generated by such a setup and they legally don't have to do anything to help you resolve your interference issue (if this is the case).

However, most hams are friendly people (aside from always talking about their antennas too much) and if this were the case, and you could locate your local ham, they'd probably be more than happy to help you resolve your interference issue.

Also, if you wanted to see if you can stop the interference through filtering yourself, you could put a broadband RF choke on your power cord to filter out any interference coming in through the mains. In fact, even if it isn't a ham doing this, it might help solve the problem.

Some sound samples of amateur digital transmission modes are available here so you can compare.

I've experienced the interference firsthand myself, by being an operator. If I key up in the lower HF bands, my touch lamp will flicker and cycle, my speakers will all buzz, even my subwoofer that is turned off in sleep mode will wake up and start buzzing like there is no tomorrow, and that is on anywhere from just 5-100 watts of output power!

Hi Guys, Just a suggestion before giving up and sending it back, have you considered adding some clip-on Ferrite cores onto the cable to see if it suppresses the RFI/EMI noise?
I noticed the my Huion Kamvas Pro 16 cable doesn't have any ferrite cores on the ends of the cable but I personally haven't noticed any interference of ghosting and am not sure if the Pro20 cable is also missing them.
I did notice online that the Wacom tablets all have them on each end of their cables so perhaps they would help?
Amazon sells them in kits for various size cables, like this one:
https://www.amazon.com/gp/product/B07CWCSNW9/ref=ox_sc_saved_title_1?smid=A1S74XD9IDUGLD&psc=1
I really think adding one on each end of your cables along with any other monitor cables you use that might be missing them will help to get a pristine interference free image.
I hope this helps, Good Luck!

I'm using a 2i2 and not having any issues like this. I just tested it, and even with using a Shure SM58 (very different mic, SM58 is a vocal mic) and plugging in my acoustic electric the first few seconds of the track are completely silent on both channels.

I'm not much of an expert here but you may have either electronic or literal background noise. I used to run a Dean Markley Soundhole pickup to amp my acoustic guitar and it would have interference, and I just picked up a couple of ferrite cores from RadioShack for like $5. They seem like some kind of magic, but the magnetic ferrite core just snapped onto the line cord fixed my problem. You can find them on Amazon for like $4.

http://www.amazon.com/Ferrite-Core-Cord-Noise-Suppressor/dp/B0002MQGE0/ref=sr_1_4?ie=UTF8&qid=1449275303&sr=8-4&keywords=ferrite+core+1%2F4%22

The second thing may just be the fans on the laptop or anything else in the room. I'd try changing the power settings on the laptop to low power, that uses less energy and will spin the fans at lower rpm making them quieter.

Finally, I'd try the Line and INST selector switches as I think that might be part of your problem. I'm not much of an expert, but here's the manual page on the two options.

> The front panel input sockets are Neutrik Combo®, which accept either an XLR male connector (you
will probably have one on the end of your microphone cable) or a ¼” (6.35 mm) jack plug. Note the
Scarlett 2i2 has no “Mic/line” switch – the Focusrite preamplifier stage is automatically configured
for a microphone when you plug an XLR into the input, and for a line or instrument when you connect
a jack plug. Set the LINE/INST switch next to the socket to INST if you are connecting a musical
instrument (a guitar in the example) via an ordinary 2-pole (TS) guitar jack, or to LINE if you are
connecting a line level source such as the balanced output of a stage piano via a 3-pole (TRS) jack.
Note the Combo connector accepts both TRS and TS types of jack plug.

I'm fairly sure if you're using the SM57 mic it's using an XLR connector, what you definitely don't want is some kind of adapter that changes it from XLR (the three prong cord) to a 2-prong TS or TRS jack. XLR is a balanced cable and shouldn't have as many problems with interference. It seems like with XLR it doesn't matter what the selector switch is set at.

Hope this helps, good luck.

I often use a surface pro 4 with aprs. It definitely generates some RF noise though not as bad as some laptops I've used before. Something as simple as a frayed or loose cable can make a big difference though.

​

Technically yes you could install a filter between the antenna and the handheld, but I don't think thats the road you want to go down. I would start by getting some ferrite beads (anything like this): https://www.amazon.com/Cedmon-Pieces-Ferrite-Suppressor-Diameter/dp/B07CWCSNW9/ref=sr_1_5

Snap them around any or all cables coming out of the surface, see if things work better. If one helps, try two or loop the cord through it a couple times for even better suppression. You can listen on your handheld with the squelch held open and see if the noise changes or gets quieter when you put them on. Also compare running on battery vs having the charger plugged in, sometimes one will be a lot noisier than the other.

If the operator is a licensed ham and his station is in good operating order, there's not much you can do. All of your electronics have those labels on them stating that they are FCC Part 15 compliant - this means they must not create interference to a licensed device, and must accept interference form a licensed device. The law actually protects him, not the other way around.

There are ways to reduce the interference accepted by devices. Ferrite chokes are a common place to start. Wrap the leads on your speakers a few times through snap on ferrite cores (like these ). You'll also want to wrap a zip tie around the core, they snap on parts will loosen over time and the tiniest, tiniest gap renders them ineffective.

I have a link bomb of RFI prevention, along with some grounding things. That might have some helpful information for you. It generally comes down to applying lots of the proper ferrite all over.

The ham might be willing to help you correct the issue if you approach him cordially. Just nicely explain the situation. We may also be able to help some here.

I think you are going to have to make your own. Here's some links from a comment I made from a year or two ago:

Hey! Here is a guide that will tell you everything you need to do and it doesn't require any electronics knowledge at all: http://www.stepmania.com/forums/input-adapters-and-controllers/show/5493

I made two of these and they work great. With the pinout, you're pretty much set.

The only thing that I needed to purchase that the guide was not 100% on were ferrite cores - I recommend you getting these. They are little cylindrical clasps you put on to wires that help with interference. All parts linked below:

https://www.amazon.com/gp/product/B016FBVIJY/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B00UUROWWK/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

https://www.amazon.com/Gino-Suppressor-Ferrite-Filters-a12071000ux1058/dp/B009ENG6TI/ref=sr_1_6?ie=UTF8&qid=1474499132&sr=8-6&keywords=ferrite+core

edit: here is the pinout for the cobalt flux http://pinouts.ru/Game/cobalt_flux_pinout.shtml

I spent a good while in /r/vive before receiving my Vive. One of the suggestions that was made regarding the lighthouses and jitter was ferrite beads.

I am in a metropolitan area, but more importantly my subwoofer used to play what sounded like a radio station when it was not being used by my receiver. This lead me to believe that ferrite beads were a good investment for my lighthouses(to mitigate interference there). I bought this pack -

Ferrite Beads

I used about 4 of the ferrite beads on the subwoofer and it is no longer audible when the receiver isn't using it. I placed two ferrite beads on the power cords for each Lighthouse and have had nothing but good experiences with my Vive. Although I haven't tried without the beads, I experience no jitter.

I wouldn't have given this suggestion much thought if it wasn't for the fact that a Valve engineer actually responded and seemed to agree that RF can interfere with the lighthouses.

This is the thread I am referring to -

https://www.reddit.com/r/Vive/comments/4ghqyc/strong_rf_pollution_from_a_radio_tower_might/

Is it GSM noise like 30 seconds into this video? If it is, you may have some luck suppressing it by adding some ferrite beads to the various cables: http://www.maclife.com/article/iphone_buzz_kill.
Easier to use snap-on ones like these rather than harvesting them from other cables.

You should get some ferrite cores. Put one on each end of the cables (your charger and your audio cable).

It's most likely engine noise entering the charging cable, but it could also get picked up by the audio cable.

You can try different schemes. It may be placebo, but I think they do best when they have one wrap around the core, like shown here.

Yeah, it's basically an EARCHI end-fed 9:1 antenna. I rent a room of a house so have to be fairly temporary with my set up, but I use an enclosed patio as my shack, feed 25 feet of coax out the window, have the matchbox on the balcony rail (supported by looping the coax), then tossing the wire about 30 feet up into a tree. I run it with an IC-7100 and an LDG AT-200 tuner.

From Kansas, I've made digital contacts into Eastern Europe and voice all over the US.

Because of how much I travel (3 months on the road year to date) and my housing situation, I have my set up so that I can easily set it up and take it down whenever I want to play. The only thing that I leave "permanently" is fishing line to pull the antenna wire up into the tree so I don't have to mess with that every time.

ETA: The only two parts that can't be easily found in a Home Depot / Lowe's are the SO-239 panel mounts ($12 for 5) and the T130-2 toroids($14.59 for 4). You can use any PVC junction box or enclosure, then add some wire and the miscellaneous hardware and have enough materials to make an end-fed and multiple types of dipoles if you want to experiment further.

Before you give up completely, try a ferrite bead on power cables, and maybe even the XLR. It sounds silly, but they’re cheap and easy to use. They just snap on the outside of your cables, with no modification needed. So if it doesn’t work, it was only like 5 minutes of work, and like $10.

My bet is actually that you have poor shielding somewhere else in your system, and this is simply being manifested via the mic input having AM radio noise.

You can get a variety pack on Amazon for $10. I’m sure that you could find smaller packs for less if you looked around. That was simply the first result I saw.

Look for an inductor. However, if you just want to order some torroids to wind yourself I've used these which are a nice size for easy winding and work just fine.

Way cool! Thank you. I couldn't figure out the proper name for them. I just ordered some off of amazon ;) Link.

DisplayPort cables are extremely sensitive to EMF, and switching a light on and off causes a spike. If the cable isn't well shielded enough, this can happen. Try picking up a ferrite ring (you don't need 15, and these might not be the right diameter for your cable, but something like: https://www.amazon.com/Bluecell-Magnetic-Ferrite-Suppressor-diameter/dp/B00MFCD56C ) and clamping it onto the DP cable and see if that helps.

I have a bunch of these on hand from some other projects... will they work as well?

It's not normal speaker wire, I'm using these (supposedly shielded) instrument cables, running to powered studio monitors. Will that work with the ferrite rods?

Nope, you're not doing anything wrong.

That's just a combination of:

• various noisy electronics around you
  
• the rtl-sdr dongle's internal noise from it's circuitry
  
• some noise from the computer/monitor you're currently using
  
  A common topic here is how to reduce that noise. Usually getting ferrite beads and clipping them around various cables will help reduce noise, but it's just a common thing.
  
  Eventually you get really good at seeing what's a likely signal and what's just noise.

is it a good radio station? If so, enjoy :-)

cable may be acting as an antenna, try using a [ferrite core] (http://www.amazon.com/Ferrite-Core-Cord-Noise-Suppressor/dp/B0002MQGE0) to suppress EMI. Make sure you get the right size!

https://www.amazon.com/Ferrite-Noise-Filter-Cable-3-5mm/dp/B01N0AV746/

Put one of these on each end of your USB and speaker wires. Your wiring is acting like an antenna and picking up his transmission. Ferrite beads/chokes will help filter that out.

Sounds like RF noise from the 19V converter getting into 12V power. Maybe buy something like this for both the power leads to your laptop and the camera.

I'd like a solution too. I've added ferrite cores (https://www.amazon.com/Ferrite-Core-Cord-Noise-Suppressor/dp/B0002MQGE0) to the supplied audio cable and I still get hissing and popping.

amazon? ebay?

link link

I'm not sure this will solve it 100% but it's worth a try. If not return it or go to a shop near you and ask for this and if its possible to test it out and return it.

Gotcha, thanks for the reply.

I have a feeling you're right, and that it's due to the cheap front audio cable getting interference....and that the new GPU i installed pumps just enough power to make it more noticeable.

I have some new monitor cables coming in...so I will see if they make a difference, if not I will try to get one of those ferrite chokes to see if it makes a difference.

I also haven't taken off the front panel to give simply "jiggling the handle" of the front audio cable a shot to see if it changes anything.

Maybe looping the wire around a ferrite bead may help?

If it turns out to be the phone, check out the Ferrite Beads like these which help suppress this noise.

Getting a Pack of Ferrite Cores for your cables might help to reduce/filter the EMI from nearby cables and devices. I used to have a very similar issue and this fixed it.

Before you go out and spend a bunch of money, try putting a ferrite core on the USB cable. I'll update this post with a link to something that might work.

Edit: http://www.amazon.com/gp/aw/d/B007Q94DBK/ref=mp_s_a_1_3?qid=1375477435&sr=8-3&pi=SL75

Something like that. If your local radioshack has a parts bin then they should have some.

Random shot in the dark, but...

Get yourself pone of these (or something similar - can always yank one off of an old power cord too) and wrap the USB wire through the center of the core twice.

Its possible there's some interference traveling down the ground wire/shield and into the speakers even if its not an analog audio connection.

Try a front USB port instead of a back one, or vice versa.

There is also the possibility that the card is dragging the system down and not giving the USB chipset enough resources to handle the audio stream. Try updating drivers for the USB device as well.

Use a USB extension cable, like this, and clip a ferrite choke on each end. Route the USB such that it doesn't cross, or ideally, come anywhere near any power cords or transformers, and place the dongle as far away from the PC as you can.

It'll help a bit, but it's still a $15 piece of hardware, and as such, won't be perfect.

Buy some ferrite cores (check the right diameters), wrap them around the power cable(s).

https://www.amazon.com/gp/aw/d/B07CWCSNW9/ref=sspa_mw_detail_6?ie=UTF8&psc=1 I used a couple of these on the radio power cable.

Ferrite cores are legit. They cost $0.50 each on amazon and don't introduce another connection in the signal path.

https://www.amazon.com/Ferrite-Core-Cord-Noise-Suppressor/dp/B0002MQGE0

Very much this. Add some ferrites to your USB extender cable and you will also reduce some of the background noise.

Expensive? Not sure if the diameter matches, but here’s a pack of 5.

I know, right? I'm not sure how it's happening. I'll try to get in touch with Lutron who makes the dimmer and see what they say.

I have no idea but would a ferrite snap work?

5 Pcs Clip On EMI RFI Noise Ferrite Core Filter for 7mm Cable https://www.amazon.com/dp/B00MJVLXDQ/ref=cm_sw_r_other_awd_EnI5wb28JTWF0

Okay, so that does sound very similar to the linked threads and like nothing in particular I've heard about. But because I'm completely committed to not doing work at work I burned through a lot of the comments and similar threads and found Alan Yates answer here https://www.reddit.com/r/Vive/comments/5ntjsv/losing_tracking_until_i_cover_the_room_in_foil/dcemoxn/

that specifically mentions FT 240-31. Yours in the included link it type 31 but no mention of the FT 240. So maybe that would work?

But what I would personally do is spend a bit extra to get these (https://www.amazon.com/Fair-Rite-Toroid-Core-FT240-31-Ferrite/dp/B01959LAFA/ref=sr_1_2?s=industrial&ie=UTF8&qid=1523984092&sr=1-2&keywords=FT240-31&dpID=31tzxlnmB5L&preST=_SX342_QL70_&dpSrc=srch) because it's specifically what Yates recommends.

I'd see if that works. If it does then we at least know what the problem is. Then I'd consider getting the extra link box if I found cable length to be an issue.

Sorry it was late lat night when I posted. I have a AudioFire 2, and I found that if I didn't disable the onboard sound in my bios then I would get that sound. Even if OS X doesn't detect your sound (Realtek) it is still active on your motherboard.

I also have now added ferrite chokes to all audio and power lines going in and out of my computer to my amp. This includes firewire and usb cables. I actually bought new firewire and usb cables that had the ferrite chokes already in them, the link from below was for all of my power cables.

http://www.amazon.com/gp/product/B0002MQGE0/ref=oh_details_o02_s00_i00

It's probably not one of the internal wires - it's usually the speaker or headphone wires. They will draw signal (energy) down into the sound system which then gets pumped back into the speakers. The cure is one of these. You can find them built in to most vga cords. On older electonics this piece was still removeable, so you can steal one from an old monitor or printer if you have one. If you can find one I will tell you how to properly install it.

It could also be poor grounding on the motherboard, or the motherboard could be grounding out on the case if it wasn't installed properly. Electricity is funny stuff.

Build this antenna. The isolation transformer is here. 100 ft of common RG-6 is dirt cheap. All the parts you can get from Lowes, Home Depot, Ace, etc.. The Fair-Rite #73 core you can buy from Amazon here. Wire is here. You gonna have to learn to solder - consult YouTube.

Now all you need is an average radio. I have built this antenna and listened to people 6,000 miles away.

If he's willing to throw $3.50 at the problem (and wait a couple of weeks for shipping from China), have him try a set of ferrite cores. You clasp one of these around the mic cord near the point where it plugs into the computer, and it can block out a lot of RF interference.

is it an HDMI monitor? If you have audio cables you can try clipping a ferrite bead on it.

If you get a lot of buzzing and there's no interference than it's mostly likely a failing speaker.

My advice?

1. Don't buy a car for $1000. It ain't worth it. You'll have problems that will cost you far more than $1000 to fix in parts alone. And your time isn't free.
   
2. There's little in the 6m world that isn't also HF. So may I make a suggestion: The Icom IC-7100 is less than $1k, works all bands even in weak signal mode (even 2m/70cm), and is a damned solid radio. You can even put it in that $5000 beater you intend to buy (any less of a car and you're going to suffer greatly).
   
3. Or, you know, you can try a little less hard about that mobile rig and go with a Yaesu 857-D. But it's a wee bit harder to use (though far easier to mount).
   
4. Or get yourself a Used IC-7200. HRO has a few in stock, and they're still solid radios (despite being superseded by the 7300).
   
   Or, you know, you can do the right thing and buy an IC-7300 like everybody else.
   
   As for antenna, the ARRL antenna handbook has a LOT of great designs that aren't so hard to make yourself. In particular, the ARRL's Antenna Handbook, 23rd Edition has some designs for you in section 15 and 16. Section 15.2.2.2 discusses the workhorse J-Pole antenna. Section 15.3.3 includes information for 6m Yagi designs (and table 15.13 gives you some info about 4 element Yagis). Section 16.6 even includes full specifications for a halo antenna that they claim to be suitable for mobile use.
   
   Hell, winding up a 9:1 unun and feeding it into a decent length of wire + counterpoise on the other side will do the trick quite nicely. I used that design to wind my own. Don't bother making the guys in Honolulu ship it to you (because shipping from Honolulu is a pain in the ass regardless of where you live), though do kick 'em a couple bucks if you use the design. (You can get the parts here.)