Evaluating Clip-On Ferrite Beads with your nanoVNA (075)

[@WECB640]

Whenever I see that Ralph has posted a new video, I stop whatever I'm doing, sit down and pay attention. There is always so much to learn and his videos are consistently exceptional. 73 OM 👍

[@eie_for_you]

Thanks! That is very encouraging. 🙂

[@mikesradiorepair]

One thing I learned a long time ago, buy name brand ferrite. Only thing in use in my shack and on my work bench's is Fair-Rite brand. Buy once, cry once. Well worth the additional cost in my opinion. The three handiest mixes for use in amateur radio are type 31, 43 and 61. Just be sure to pick the correct mix for the frequency of concern.

[@eie_for_you]

Great advice! I cannot agree more. Ya get what you pay for! 🙂

[@Conjugate-Match]

Ralph, I'm sure you know this already, but I'll state it for the benefit of your audience. 3 turns of a wire through a single ferrite would be MUCH more effective than a single wire passing through 3 ferrites. If you're shopping, buy larger diameter ferrites and wind your wire/coax through as many time as it will fit, I recommend a minimum of 3 turns for good attenuation. Type 31 and/or 43 are great for common mode or noise attenuation in the ham bands. I really like your testing jig, and will make one. The multi-turn effect could be easily demonstrated using it. Thanks for your very informative channel. I enjoy one or more of your vids just about every day.

[@eie_for_you]

There ye go! Each additional turn adds some benefit. But, it is the law of diminishing returns, as I show in the video. Yes, each additional turn adds more benefit, but less than the previously added turn. 🙂

[@echadmiyodea]

When you say "turns" you mean winding the wire through the hole and around the outside of the body of the ferrite, as in repeating loops through the ferrite?

[@eie_for_you]

@@echadmiyodea Each pass through the ferrite is a "turn." The key is that the wire passes *through* the ferrite. Having it beside the ferrite, on the outside, doesn't count. 🙂

[@Electrotech1980]

Great job, thanks.I had a problem with my washing machine on 80m. I purchased from Mouser 2 clip-on ferrite beads that worked best at low frequencies. The idea was that I was able to look at the datasheets with curves. I then clipped them on the power cord of the washing machine, with 2 wraps each. It worked. Buying a known ferrite is the best!

[@eie_for_you]

I LOVE the success stories! 🙂 I wish I could put a ferrite on the entire city of Dubuque! We have an S7 to S9 noise level here and it is guys to the south of the city and guys to the north all have the same issue. I've turned off my own main breaker and ran my radio off battery ... no difference. 😞

[@arnoldgrubbs2005]

@@eie_for_you I know of what you speak! Keep after it, you will find what it is eventually! I have had s7-s9 noise here in my town, which is power line induced. It changes with weather, and seems to follow a HV feeder that passes my house about 300 ft to the east of my house . 4 or 5 blocks on either side of the line, the noise tapers off. It also reduced a lot last spring, but it seems to be coming back. Interesting thing, I had the power line drop coming to the house from the alley put underground (at my own expense) to give me more room for antenna construction, and while that was in process I noticed my neighbor had his power drop from the pole to the house and it was rubbing on a large tree limb. I noticed also that someone (doubt it was the utilities people) had wrapped what looked like part of a rubber door mat around where it contacted the tree and secured it with zip ties. So, I will be looking at this a little closer when the weather warms up this spring! I suspect that there was or is still leakage to the tree when the tree is moving in the wind, and it makes its way back to the feeder by the transformer in the alley passing the noise to the primary side. It then radiates out from that line which runs to a much larger substation 5-6 blocks north of me. 73 and good hunting!

[@eie_for_you]

@@arnoldgrubbs2005 I hope to do a mobile search with my RF Explorer and a portable antenna....sometime! 🙂

[@RBMD2A]

Excellent video.

[@eie_for_you]

Thanks! 🙂

[@SkyhawkSteve]

VNAs are great tools, and the availability of the inexpensive ones is great for the hobbyist. As for ferrites, I spent a lot of time working on EMC problems, and a selection of clip-on ferrites is very handy. Our lab used Fair-rite ferrites mostly. You do need to select the correct material for the frequency range of interest, and you should select the ferrite that fits snugly around the cable. The impedance of the ferrite will be reduced when there is a gap. As you note, you do need to read the data sheet and understand it. Measuring the ferrite is useful, but be aware that they usually have a large tolerance. I recall that a tolerance of 25% was pretty typical. It's more useful to just buy a good ferrite from Fair-rite or Wurth or other reputable supplier.

[@eie_for_you]

Thank you for the great advise! I cannot agree with you more. 🙂

[@TH-1207]

I don't recall you mentioning anything about the ferrite material. That makes a big difference too. A question how much difference does the split core make. They are convenient but at what price to performance?

[@eie_for_you]

I did, indeed, make a note to pick the right material for the job. Good point about the split core. I would assume that the split core is a compromise for the convenience of being a clip on. I'm not sure how much that affects overall performance. 🙂

[@johnclements3441]

Excellent! Never thought of putting one on a VNA but makes sense why my cheap Amazon ones provided little real value.

[@eie_for_you]

Thank you! 🙂

[@meinsda5983]

Very interesting your video! But whats the difference if you put in and out throuth the ferrite?

[@eie_for_you]

Thank you! Putting the wire multiple times thought the ferrite is similar to adding ferrites to the wire. It sounds like a good experiment for your bench! 🙂

[@meinsda5983]

@@eie_for_you i don't mean that you multiple times. You have a output signal, go thourh the ferrit and goes to the input of your mesure instrument. The current goes over GND in the intstrument back. But look of the most time used. The roudn trip line goes thouth the ferrit.

[@eie_for_you]

@@meinsda5983 Hmmm...I'm not quite getting what you are trying to say. 😕

[@marcfruchtman9473]

Interesting. Thanks for the video.

[@eie_for_you]

Thank you ... and you are very welcome! 🙂

[@qutips33]

hi thanks for the info. i have a question for you is it possible to use rig ekspert stick 500 to measure db deping through ferrite cores ?????

[@eie_for_you]

You need a 2 port measuring device to do this measurement. The Stick 500 is a single port device; it measures things like SWR, return loss, impedance, and the like. It cannot measure things like filter frequency response. This ferrite business is, in essence, a frequency response-type test. 🙂

[@peterdambier]

Very helpful. I am experimenting with Flowerpot Antennas for 2m and 70cm and for digital vhf radio. I guess they will do the job but they are not great. Cherio, Peter DL2FBA

[@eie_for_you]

Cool! 🙂

[@ehsnils]

Good idea. It did look like the wire wasn't insulated and I'd probably like to run an insulated wire just to make this more realistic. I have purchased my ferrites from a source I think is having a decent assortment. I did pick them based on the quality impression they gave and not on what they stated on ebay or some other grey web trading site like the jungle site. (Robot Cantina name for a well known site)

[@halledwardb]

Cool another project I can do with the girls! Our lives could be better at 14mhz around this house. 😂 Thanks!

[@eie_for_you]

I'm glad that you found this video helpful ... and fun! It was most certainly a fun one to produce. 🙂

[@Grassland-Outpost]

But, but … mix 31 clip-ons are expensive. :-). Great video, I’ve wondered about how to easily test them.

[@eie_for_you]

Yeah ... they aren't always a cheap as we would like, but if we want to get the job done, we have to pay the price, eh? I'm glad that you found the video helpful. 🙂

[@SQ5TK]

Great video, thank you.

[@eie_for_you]

Thank you! And you are welcome! 🙂

[@EI6DP]

Very interesting.

[@eie_for_you]

Thanks! 🙂

[@ea77hj]

Good and enlightening tutorial. Grateful. Any ferrite that works well in HF? Which of them should we buy? Thank you so much. EA7HJ

[@eie_for_you]

Thank you! Here is a quote from one of the other comments that might help ... "The three handiest mixes for use in amateur radio are type 31, 43 and 61. Just be sure to pick the correct mix for the frequency of concern." When in doubt, contact the manufacturer. They are often very helpful in selecting a ferrite for your application from among their products. 🙂

[@ea77hj]

Many thanks. 73

[@eie_for_you]

@@ea77hj You are very welcome! 🙂

[@Notmy00000]

🙏🙏🙏🙏from 🇳🇱NL

[@StephanLuik1]

If you need clip-on ferrites to solve a problem, then the circuit design is bad.

[@eie_for_you]

True that! But we often have no choice but to accept the shortcomings of other people's designs. Thus, we are stuck with clip on ferrites. 🙂

[@GworxOz3953]

Please keep your silly bible bashing to yourself.

[@eie_for_you]

🙂

[@TrygveMedhus]

Exelent! But stop promoting your fantasy figure. It's just annoying.

[@eie_for_you]

Thank you! I'm glad that you found the video helpful. I'm not sure I know what you mean by promoting my "fantasy figure." 🙂

[@hankhamner3671]

This is a dumb comment. The presenter did a great job!

[@eie_for_you]

@@hankhamner3671 🙂

[@railgap]

I think you commented on the wrong video or something.

[@eie_for_you]

@ 🙂