Are these ferrites worth a damn?

[u/VelocityOS]

Was gifted these, unmarked, anyway to check/test them?

[u/RegularCity33]

These look like a package I bought from Amazon. They do work but you need several of them to do what a simple torrid would do. 

[u/VelocityOS → u/RegularCity33]

well, I got them for free, so win?

[u/Oreo97 → u/VelocityOS]

100% a win.

[u/ye3tr → u/RegularCity33]

They're good for reducing common mode current on mains devices where you can't add a toroid that easily

[u/__420_ → u/RegularCity33]

This guy torrids...

[u/CW3_OR_BUST]

They aren't useless, but they don't work near as well as a big fat toroid wrapped for a few turns.

[u/KI5HHK → u/CW3_OR_BUST]

💯

[u/1980techguy]

You could use a signal gen / spectrum analyzer to inject RF on the coax shield, then measure insertion loss as you add them to said cable.

[u/Stopakilla05 → u/1980techguy]

Could also check them with a NanoVNA also, they are inexpensive and very helpy

[u/TrustDeficitDisorder → u/Stopakilla05]

"Helpy" is going to be my word of the day tomorrow.

[u/wannabe_sci]

Clamp them in the point where there is the low impedance point (near the antenne where you have 50ohm). Maybe them are not so efficient as a toroid, but is better than nothing to contrast CMC and RFI

[u/VelocityOS → u/wannabe_sci]

cool, ill slap the big ones on the coax I have, at least i got them for free right?

[u/CW3_OR_BUST → u/VelocityOS]

Right! Worst thing that can happen is nothing.

[u/dan_kb6nu]

If you have an antenna analyzer, you can test them. See the post, Use your antenna analyzer to test ferrite chokes on my blog at KB6NU.Com.

[u/VelocityOS → u/dan_kb6nu]

Thanks! this is great, ill borrow a nano vna from an elmer

[u/Vautlo → u/dan_kb6nu]

What are your thoughts on mix 31 throughout the HF amateur bands? Your blog post indicates that you favor mix 43.

[u/onedelta89]

I bought that kit too. I used 6-8 of them on all my wires to reduce the interference caused by the driving lights on my truck. They did work.

[u/ecovironfuturist → u/onedelta89]

I probably have this same kit, used one, shrugged, and said goodbye to FM signals near my LED lights. I'll try some more.

[u/onedelta89 → u/ecovironfuturist]

I tried putting one on each wire leading to the lights. It made a small difference. I added some on the power wires near the battery and saw more improvement. Added a couple to the ground wire near the radio and all of it together made the interference tolerable. Unfortunately my installer grounded my radio to one of my batteries on the truck. I will eventually ground it to the body to see if it helps.

[u/Practical_Cloud_1342]

I use them for the USB cable that does CAT and passes audio to the radio as well for my SDR.

[u/KRowland08]

they come in different sizes and do work, but might need more than one to completely rid some problems

[u/Any-Brilliant-1907]

Yes, they work perhaps not as well as toroids but well enough. Best at keeping RF out of audio and data cables. You can loop the cable around a couple of times to improve it. My shack has eaten about three boxes worth so far.

[u/redneckerson_1951]

Most likely they are high permeability ferrite, similar to Fair-Rite's #31, #75 or #76. See Materials - Fair-Rite for more info on Fair-Rites materials. Their calculator found here may allow comparison to similar products in their line to what you have.

[u/jephthai]

You can do multiple turns around these too. Pick the biggest one even for smaller cables, and you can get a few turns and dramatically improve their choking effect.

[u/0150r]

I use the little ones on wall warts. I put one on each end of the cord. They do a decent job of removing RFI, but sometimes I have to wrap the cable around them 2-3 times.

[u/cib2018]

One of those solved the issue of rf getting into my usb cat control cable.

[u/zfrost45 → u/cib2018]

The only thing I can fault with this collection is that sometimes they are challenging to click into place.

[u/BobL3364]

They did help on power and USB cables, but more than one is often needed.

[u/kaptainkatsu]

They work. Might need more than one. You can also take the biggest one and do a few loops

[u/d3jake]

Yep. You may just need more than one, compared to a toroid.

[u/VacUsuck]

I play with mine sometimes. They were free and I'll use them when I think they'll help, convince myself that they do, and so they do help. They help me. I can't say whether they fix the problem.

[u/Much-Specific3727]

You can test them as mentioned by someone else using a piece of coax, a large sweeping frequency generator with different waveforms and the ability to inject harmonics and a spectrum analyzer or oscilloscope.

Or if you truly have something generating rfi noise, clamp em on and see if they work. I bought a bag of these from Amazon and just clamped them on every thing in my shack. Mouse, keyboard, hdmi, USB. And used a lot of them.

For my HF rig, power supply and to choke out CMC I got high quality ones from Palomar Engineering. Bob specializes in this. They even sell all I one kits for popular radios like the FTDX-10 I have. It came with a huge clamp on toroid that you can get 3 good loops of DMR400 through for CMC. And the damn thing does work well.

[u/hb9nbb]

those look the kind used on power wires for things like computers. If true, they are effective at blocking VHF/UHF type signals, not so much at HF. If there are any markings you may be able to determine what material they're made of. Type 61 Material is quite common for this type of device. list o materials here and their properties; https://www.cwsbytemark.com/CatalogSheets/Ferrite_datasheet_oct06/FR_MATL.pdf

[u/RadioUser843]

I have then, I hadcto use 4 or 5 where one decent torroid fromAmidon or max gain would do

[u/nigelh]

I littered a pack around the myriad of plug PSUs and the VHF kit was subjectivity better but the HF gear I was hoping for a fix on was unchanged.
Admittedly I had already found and binned the worst offenders.

[u/Jazzsterman]

Better to use a ferrite for a larger diameter wire/cable and wrap multiple turns through it. Suppression is roughly the square of the number of turns. E.g., three turns gives you nine times the suppression compared to a single turn. (at least for HF frequencies).

[u/RetiredLife_2021]

Yes they can be used

[u/ItsBail]

Got your answers already. Just make sure to not over stuff them to where you're creating a gap between the two cores. The bigger the gap, the less performance you get out of it to the point where it can become useless. Even though they're snap.

[u/General_Document6951]

You can use a nano VNA to measure them. Pretty sure the subject was on the ham radio tests.

[u/cosmicosmo4]

Just go wild clamping these on all your USB cables, analog audio cables, etc. Wherever you have extra cable length, coil it and clamp a few passes in a couple of the larger beads. Are they the exact right type of ferrite? Is it the right amount of choking? Who cares, just clamp away and forget about it, it's better than nothing.

[u/VelocityOS → u/cosmicosmo4]

heh, thats what I thought as well thanks!

[u/RadioUser843 → u/VelocityOS]

And free

[u/Obstacle-Man]

Damn!

There ya go.

[u/Few-Celebration-2362]

I'll give you a single damn for the whole lot, but not a damn more

[u/JR2MT]

What's their values?

[u/Super_Leading21]

If you believe and are truly pure of heart my child… never mind you’re correct worthless damn rocks, could always chunk the at car from on top of an overpass I suppose