Recyling scrap Ferrites? - Page 1
Forum section: electronics / general

author: TerraHertz
author_rank: Super Contributor
timestamp: September 21, 2017, 03:01:37 am
content: During another junk cull to free up space, I just stripped down a dozen old CRT yokes. Plastic bits go in the recycling roley bin, copper goes to the metal recyclers, but what to do with the scrap ferrites?It always makes me feel bad throwing this kind of stuff in the rubbish bin. Ferrite strikes me as one of the worst e-wastes, since it's so permanent. This stuff will probably outlast rocks. Also, what are the component elements, that might (slightly) leech out in landfills?So, before I bin these, can anyone think of creative recycling uses for scrap ferrite pieces?Ha. If one had enough of it, perhaps crushing and adding to concrete, to make magnetically shielding structures might appeal.

author: station240
author_rank: Unknown
timestamp: September 21, 2017, 03:15:12 am
content: I always just dumped mine in the scrap steel/iron pile. Not so bad as it is mostly Iron anyway.

author: amyk
author_rank: Super Contributor
timestamp: September 21, 2017, 03:23:10 am
content: I thought the title was "Recycling scrap Ferraris"A long time ago I remember reading that the FCC (in the US) used to give them away free for people to put on their power cords etc. to reduce EMI.

author: Brumby
author_rank: Unknown
timestamp: September 21, 2017, 03:48:45 am
content: You could always dip them in this stuffand sell them to audiofools as power lineinterference filters.Have the banner selling point as being theunique semicircular 180º phase cancellingdesign.You'd have to charge a minimum of ...???Hmmmm ... that's a good question. Whatfigurewouldyou put on that?

author: daqq
author_rank: Super Contributor
timestamp: September 21, 2017, 07:04:00 am
content: QuoteThat might not actually be a bad idea - what would be the properties of a material that was ground ferrite dust suspended in a binding agent? I'm looking into ferrite cores and they do actually make a distributed air gap material. Stealing from another thread:QuoteMaybe you could recycle them into some kind of shielding, absorber?There are also rubbery materials with ferrite properties ( see:https://www.eevblog.com/forum/reviews/ferrite-hot-snot-emc-begone!/), so you might actually make something interesting, with hot snot and ferrite powder.

author: cdev
author_rank: Super Contributor
timestamp: September 21, 2017, 04:58:15 pm
content: There is one sleeve like toroid I got from a broken fax machine some time ago, that I seem to have lost somewhere in my stuff, which was particularly good for use with a magnetic loop.The loop passed through it and a single turn of wire around the loop made with a BNC to banana plug adapter linking it to my receiver worked spectacularly.That loop was an exceptionally good performer with that specific toroid.So good that I think maybe that shape, similar to what your ferrites there would look like if put back together had some advantage in that context.I would consider taking them and putting them back together with a bit of glue. Another use is filtering RFI. I have a tremendous problem with RFI on the mains where I live..So, assuming it fit, It looks like it might, but likely tightly, I would put some of them around the PVC sheathing around the power line coming in to my house to attenuate a bit of the RFI that comes in on it. Every little bit helps. It would save having to saw one apart and re-assemble it.They look like they have marking on them, maybe you can get an idea of what material they contain?If they use a mix thats useful, and fit together with glue, perhaps I'd re-assemble them?Here you can see how much a decent toroid costs from avery low priced seller.They aren't as cheap as one would wish!

author: AllTheGearNoIdea
author_rank: Unknown
timestamp: September 21, 2017, 08:22:15 pm
content: Radio hams used to use yokes as coax balun's

author: Bud
author_rank: Super Contributor
timestamp: September 22, 2017, 01:21:12 am
content: Yes they have decent attenuation over the Ham radio HF bands.

author: Bud
author_rank: Super Contributor
timestamp: September 22, 2017, 01:34:43 am
content: Quote from: cdev on September 21, 2017, 04:58:15 pmI also use them with power strip extention cords wrapped a few turns around the core and secured with plastic ties. I'd think RF chokes made in that manner placed on LED light panels power wires should do a good job in the shack as RFI suppressors. You can place them everywhere around the bench on power wires in the shack in fact, at zero cost.

author: TAMHAN
author_rank: Frequent Contributor
timestamp: September 22, 2017, 02:24:43 pm
content: That is what I wanted to suggest. I have a lot of LED lighting in my office, and it fucked up my LeCroy and other sensitive instruments. Now that I "reintroduced" ferrite bead shielding, the problem is an ex-problem...

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 22, 2017, 03:46:10 pm
content: It's too bad that yoke ferrite is some crappy grade. Not high permeability, and the shape is inconvenient for power applications (besides the taper and the high aspect ratio, the path length l_e is rather high, too).Hmm, another sad thing about that pile: the halves are actually pairs -- note the fractured ends? They aren't ground flat, so they only fit tight when they're from the same original whole.At least that doesn't matter as much as it would for regular core shapes, because of the mu and l_e.Tim

author: cdev
author_rank: Super Contributor
timestamp: September 22, 2017, 04:57:15 pm
content: It is if they are.Are you sure that the ferrites are no good for RF transformer use?EDIT:This is interesting- just found, reading it now."7 – CONCLUSIONThe yoke core is well suited to HF broadband use in baluns and transformers. The fly-back core is a high permeability material better suited to low HF. These cores can be found for free in repair shops.There's much more to discover as one delves into this subject. For the time being I'm very happy to report these findings and I thank Ian, G3SEK, for his enlightening RadCom note."-------because if they are simply #2 or #6 ferrite or #43 iron powder they could definitely be used in all sorts of things..If the material is a useful one, if he re-attached the broken pieces together, like with porcelain, IF he got the alignment and glueexactlyright, I bet the irregularity could potentially make for a strong bond because of the hills and valleys having more surface area to bond, and at more angles, and so on..I for the sake of argument, we assume that the material is a useful one, I am pretty sure that long highshape, even fluted like that would work well for all sorts of things based on the fact that Amidon, I think, now manufactures a #2 material ferrite core ("T400A-2" which presents a similar profile due to popular demand from hams who were stacking their large ferrite cores to get better results when using them in high end 160-10 meter antenna tuners.)They cost $35 each.Those cores were a special order item I think for a while. They are twice the width(?) (more tube like, less doughnut like) of the usual doughnut shaped (T-200 and?) T-400 cores and for example are used in high end high power"smatch" balanced tunersand also used by a Dutch (I think) ham who makes super expensive, highly sought after hand built transmatches/tuners that are almost works of art.- Cores that could be nested into one another somewhat might work fairly well as a unit.. if the material was a useful one.Quote from: T3sl4co1l onTodayat 09:46:10

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 22, 2017, 06:01:04 pm
content: FYI, it's really hard to tell what parts of your post are quoted and original text.Quote from: cdev on September 22, 2017, 04:57:15 pmFYI, numbered designations are Micrometals and Fair-Rite products.Most numbers are powdered iron (2, 6, 18, 26, 52), while most of the higher numbers (43, 61, 77, etc.) are ferrite.Check the manufacturers' catalogs to find out which ones are which.Other manufacturers use single letters (Magnetics), or alphanumeric (e.g., Ferroxcube 3C90, TDK N49, etc.).Other (non pure iron) powder materials fall under trade or brand names (MPP, Sendust, Kool-Mu).QuoteYes, Super Glue is an effective method for disassembling* ferrite cores.*Since, you break them as often as not, when scrapping an assembly. Thus, glue is a necessary ingredient of salvage.QuoteFYI, Amidon is a distributor; much like McMaster Carr, they don't list manufacturers and part numbers. Though in this case, it's not hard to figure out what it is they're selling (Micrometals parts, like the above, are sold pretty much straight from their catalog).Incidentally, #2 is a terrible choice for baluns at 160 meters. But it would figure that, on average, hams aren't very technically innovative. That's another one of those domains where bad advice circulates for decades, subject to little or no critical review.(Queue people willfully ignoring my above use of the word "average".)QuoteMicrometals' 'A' and 'D' versions are standard cores with taller build. (Presumably, the toroid shape is formed in a mold, and they simply fill the mold with more material to make the desired part.) I've got a lot of T68-52Ds from ATX motherboards (where they were supplying CPU core power).QuoteThis is more useful for wideband applications. You can stack different materials, extending the bandwidth significantly. Example: a nanocrystalline stripwound core (good down to ~kHz), a W or T38 or 76 ferrite (good for low MHz), a #43 or similar ferrite (medium MHz), and a #61 (high MHz). You would also use transmission line transformer techniques here. Such a transformer can be flat (say, 1dB or better) over a huge frequency range, kHz to GHz.At very high frequencies (above the impedance peak point for the material), it's also desirable to leave a gap between cores in a stack. Skin effect applies to ferrite materials just as well as to conductors, and the gap serves the same purpose as laminations in an iron core transformer. This sees use in pulse forming networks for particle accelerators.Tim

author: cdev
author_rank: Super Contributor
timestamp: September 22, 2017, 06:16:22 pm
content: Oh, this was definitely me making the mistakes, andTHANK YOU, Tim for correcting me!Below you mentioned a few things..By transmission line techniques do you mean things using a chain of magnetic material to enclose turns of a transformer - one or many- thats probably also why binocular cores make good broadband transformers, often.Also, using different materials in combination.. thats sort of the inverse of using a bunch of different capacitors to make for more effective bypassing, perhaps.Thank you for all this, you're filling in blanks for me that needed to be filled.Quote from: T3sl4co1l onTodayat 12:01:04>FYI, it's really hard to tell what parts of your post are quoted and original text.Quote from: cdev onTodayat 10:57:15>because if they are simply #2 or #6 ferrite or #43 iron powder they could definitely be used in all sorts of things..FYI, numbered designations are Micrometals and Fair-Rite products.Most numbers are powdered iron (2, 6, 18, 26, 52), while most of the higher numbers (43, 61, 77, etc.) are ferrite.Check the manufacturers' catalogs to find out which ones are which.Other manufacturers use single letters (Magnetics), or alphanumeric (e.g., Ferroxcube 3C90, TDK N49, etc.).Other (non pure iron) powder materials fall under trade or brand names (MPP, Sendust, Kool-Mu).Quote>If the material is a useful one, if he re-attached the broken pieces together, like with porcelain, IF he got the alignment and glueexactlyright, I bet the irregularity could potentially make for a strong bond because of the hills and valleys having more surface area to bond, and at more angles, and so on..Yes, Super Glue is an effective method for disassembling* ferrite cores.*Since, you break them as often as not, when scrapping an assembly. Thus, glue is a necessary ingredient of salvage.Quote>I for the sake of argument, we assume that the material is a useful one, I am pretty sure that long highshape, even fluted like that would work well for all sorts of things based on the fact that Amidon, I think, now manufactures a #2 material ferrite core ("T400A-2" which presents a similar profile due to popular demand from hams who were stacking their large ferrite cores to get better results when using them in high end 160-10 meter antenna tuners.)They cost $35 each.FYI, Amidon is a distributor; much like McMaster Carr, they don't list manufacturers and part numbers. Though in this case, it's not hard to figure out what it is they're selling (Micrometals parts, like the above, are sold pretty much straight from their catalog).Incidentally, #2 is a terrible choice for baluns at 160 meters. But it would figure that, on average, hams aren't very technically innovative. That's another one of those domains where bad advice circulates for decades, subject to little or no critical review.(Queue people willfully ignoring my above use of the word "average".)Quote>Those cores were a special order item I think for a while. They are twice the width(?) (more tube like, less doughnut like) of the usual doughnut shaped (T-200 and?) T-400 coresMicrometals' 'A' and 'D' versions are standard cores with taller build. (Presumably, the toroid shape is formed in a mold, and they simply fill the mold with more material to make the desired part.) I've got a lot of T68-52Ds from ATX motherboards (where they were supplying CPU core power).Quote>Cores that could be nested into one another somewhat might work fairly well as a unit.. if the material was a useful one.This is more useful for wideband applications.You can stack different materials, extending the bandwidth significantly. Example: a nanocrystalline stripwound core (good down to ~kHz), a W or T38 or 76 ferrite (good for low MHz), a #43 or similar ferrite (medium MHz), and a #61 (high MHz).You would also use transmission line transformer techniques here. Such a transformer can be flat (say, 1dB or better) over a huge frequency range, kHz to GHz.At very high frequencies (above the impedance peak point for the material), it's also desirable to leave a gap between cores in a stack. Skin effect applies to ferrite materials just as well as to conductors, and the gap serves the same purpose as laminations in an iron core transformer. This sees use in pulse forming networks for particle accelerators.Tim

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 22, 2017, 07:18:09 pm
content: Quote from: cdev on September 22, 2017, 06:16:22 pmNot specifically due to core type, but some cores are easier to work with than others.The transmission line approach is only concerned with the relationship between the wires. The underlying mechanism is that, at high frequencies, energy only travels in the space between wires -- the core is irrelevant to HF characteristics, and can be ignored.The space between wires is also the space where leakage inductance and parasitic capacitance arise. Indeed, these are the LF equivalent properties of the transmission line structure.The leakage inductance, of a normal build transformer (like a shell style bobbin, or toroid with full winding layers; but not so much a common mode choke, where the windings are in separate sections), is largely independent of the core. You can measure LL with and without the core, and find the measurements differ by maybe 10%.The coupling factor of course varies with the core, because the magnetizing inductance varies with the core. And thus also the LF cutoff. But the HF cutoff* is determined by the windings.*A Guanella TLT does not have an HF cutoff**, though it still has finite LL and Cp parameters. The lumped equivalent model only tells you what you can expect below HF cutoff: above, the transformer becomes a complex circuit, and may exhibit peaks and dips, weird impedances, or, in the case of a TLT, no peaks or dips at all, just a constant ratio all the way.**Well, loss in the transmission line itself, and dispersion due to waveguide modes. But that's extreme (GHz+ for most coax). Alternately, an abstract Guanella TLT, made with ideal, lossless, one-dimensional transmission line, has unlimited bandwidth.The most basic TLT is a transmission line with cores stacked on it (or wrapped around a core, or both; same thing, to the first order). This is a 1:1 transformer, also known as a common mode choke, current balun*, or semi-ideal transmission line. (The SPICE transmission line component has this behavior: there is no galvanic connection, even at DC, in the common mode, between the two ports of the transmission line. We can't achieve that in practice, but we can do a good job of it at AC.)*A particularly poor application for it, as the current can never be perfectly balanced, because the core will never have infinite impedance.If you take that and run with it, you can do tricks like, connect transmission line ports in parallel at one end, and in series at the other, to get whole numbered turns ratios. The impedance at each end is the TL's Zo in parallel or series, respectively. (So, a 50 to 450 ohm transformer is 3 x 150 ohm TL in parallel at one end, and in series at the other.)Rational ratios can be made by making suitable series-parallel combinations of transmission lines, or by cheating the system with an extra turn here or there (but you lose bandwidth then).If all the transmission lines are equal length, then the delays match, and the bandwidth is unlimited. If not, then you get peaks and dips at frequencies where the wavefronts interfere. This is the difference between a matched delay (Guanella) transformer and not (Ruthroff).The widest generalization: all transformers are TLTs, they're just really bad at it if they aren't made in the usual TLT style. A transformer made with a single layer winding for primary and secondary, one on top of the other, has useful TLT properties, and will have a wide bandwidth. A transformer made with multiple layers per winding, will have those TLT properties confined within each winding, where it's not useful (the transmission line modes are short circuited by the wire doubling back at the end), and the HF characteristics will be awful.This is one of those domains where "industry standard best practice" is almost diametrically opposite from "best physics". Another domain is electrical wiring, where noisy power switching cables are routed directly alongside control signals, for maximum EMI coupling, and where grounds are DC only (rarely continuous like coaxial shields).QuoteSort of. You don't have to worry about complex impedance, because the Q is very low (the core impedance is largely resistive). More like electrolytic capacitors in parallel.The equivalent circuit is series, but inductors in series is actually equivalent to capacitors in parallel, so you are actually quite correct there!Cheers,Tim

author: cdev
author_rank: Super Contributor
timestamp: September 22, 2017, 08:59:19 pm
content: Or a conical coil .. different properties on each end. That works better than a regular coil in a bias tee.magnetics are magic..a balun can sometimes work magic.. LOL..Quote from: T3sl4co1l onTodayat 13:18:09

author: tggzzz
author_rank: Super Contributor
timestamp: September 22, 2017, 09:39:25 pm
content: cdev, it is difficult to read what you are writing, to the point where is isn't worth people's time. Fortunately there are well established conventions that make it easier for your readers.When wishing to respond to a post, could you please locate the "Say Thanks" "Reply" "Quote" words at the top right of the post.Then click the icon next to the "quote", and insertCode: markup in the obvious places.Before clicking "Post", click "Preview" to see what it looks like.Thanks

author: TerraHertz
author_rank: Super Contributor
timestamp: September 23, 2017, 10:30:39 am
content: All very interesting, but when discussing relative merits of different ferrite materials it's over my head. I never delved much into magnetics, and have never owned or even had access to either a (working*) spectrum analyzer or network analyzer. So wouldn't know how to characterize an unknown ferrite.Improving my understanding in that field, if I ever do get suitable instruments, would be nice. Someday.(*) I have a HP 141T spec an, and a HP 8410B network an, but those were bought in my early ebay + good income days, when I overestimated my ability & time available to bring up old, old gear.I was thinking more of uses for bulk, mixed grades crushed ferrite. Since disassembling yokes is a messy, violent business, what with the glue they use to secure everything in position, and all the clipped-together plastic parts. A lot of the core halves break while being levered out. From that dozen yokes, I checked just now and there are 5 intact cores with matched halves. See pics. It's surprisingly quick to identify the matching core halves, since the feel of the matched fracture edges fitting together is so very obvious. While non-matched ones just don't fit.Using intact ones as large suppression toroids hadn't occurred to me. Will try that.Also since they are in halves that can be clipped together, how about as cores for current transformers that can be clipped around heavy AC current conductors?The other smaller yoke toroids with the four cross-field coils might have some use. If nothing else they are pretty.By the way, speaking of wondering what a compound is composed of, have a look at the mouth-watering atomic composition analyzer in these first two youtube videos. (The 3rd, also about those buttons.)watch?v=7kRy6r2e-bM What is the NEW Silver Play Button REALLY made of?!watch?v=yHA2HbNtcG4 What is the Gold Play Button REALLY made of?!?watch?v=4EL4xBxc5IA YouTube Play Button is MADE in CHINA - I went to find out where!

author: Towger
author_rank: Super Contributor
timestamp: September 23, 2017, 11:07:37 am
content: Crush them to make paint. Then paint a car with it. Sell said car on ebay as a Stealth Car. At a car foolery price...

author: TerraHertz
author_rank: Super Contributor
timestamp: September 23, 2017, 12:20:36 pm
content: Quote from: Towger on September 23, 2017, 11:07:37 amHeh. How about mixing ferrite powder with rubbery paint, and marketing it as an 'EMI Resonance Damping Miracle Coating', intended to be painted all over the outside of high end audiophoolery gear. "To achieve the absolute pinnacle of listening perfection" and so on. Mix some mica flakes, crushed quartz, or just kid's sparkle powder in, to make it look special.Think it might sell? $500 a tin?If you got the formulation right, a year after application it would turn into sticky, irremovable smelly gunk, much like that 'tactile rubber coating' that seems to have fallen out of fashionfor some reason.

author: SeanB
author_rank: Super Contributor
timestamp: September 23, 2017, 12:33:48 pm
content: You have to use a 2 part polyurethane base for the resin, so that it is something you apply after careful proportioning, so it is not for the "Average guy" either, but has to be applied by a specialist person. That way when it does degrade you can always blame application or prep, and redo it at a cost again.

author: cdev
author_rank: Super Contributor
timestamp: September 23, 2017, 01:41:12 pm
content: (this is actually a serious post, since the subject of what happens when ferrites are used in coatings and building materials came up. Likely it does do more than just "something" at GHz frequencies, I think thats likely already quite well established.)What happens when one coats a conductor or transmission line that carries signals with a "sparse" well dispersed ferrite material? Ferrite beads being "hard edged" i.e. well defined in terms of their boundaries would likely be different than a well dispersed ferrite loaded material???EM foam is made out of non-magnetic, partially conductive (carbon doped) foam. The commercial foams use gradients of foam which transition from RF transparency to high damping as he signal penetrates inward. Also their shapes are designed to increase the effects but likely a particular shape will have more of its effect at some frequencies than others.It would be interesting to mix up ferrite foam and perhaps ferrite/carbon doped combination foams of different kinds and attempt to characterize their properties.This seems like the kind of thing where once the math had been worked out for what a small volume of the material did, likely eventually a mesh could be used to model its effects in a larger context.Who knows.. So called "metamaterials" exist which have unique dielectric properties with RF. (for example, a "Luneburg lens")See alsohttps://www.aip.org/publishing/journal-highlights/device-turns-flat-surface-spherical-antenna"metamaterials" can be used to make physically smaller high gain antennas.Its already established that RF modifying materials (dielectric and conductive/resistive) make possible "lenses" for RF which behave similarly to optical lenses by slowing down the portion of a wavefront which goes through the center of this lens more than the signal penetrating it farther away, causing a bending of the signal - the focusing/gain effect.Something similar happens when a great many materials are dissolved in liquids with light, the index of refraction changes. This can be exploited to get information about them. (sugar for example, in winemaking/brewing)

author: Towger
author_rank: Super Contributor
timestamp: September 23, 2017, 02:56:57 pm
content: I don't think 500 a tin is high enough. 5000 at a minimum, remember the higher the price the bigger the fool effect.Sean, there are no real trick to using two part epoxy paint. Many a tin of International Yacht paint I have applied. Actually the trick, if using brushes is to have lots of cheap ones and just chuck them out when they start to gum up.I have also been lead to believe that proper Made in the USA Stealth Paint is water based and if you accidently leave your B2 out in the rain it requires a new expensive paint job.I think the police here don't use radar based speed guns any more, but I am sure that does not matter to the target customers demographic.

author: cdev
author_rank: Super Contributor
timestamp: September 23, 2017, 03:17:56 pm
content: I would love to see screenshots of these audiophool excesses.People could use screenshots to give the rest of us a way of seeing the most outrageous audio-phoolery without linking to themQuote from: TerraHertz onTodayat 06:20:36>Quote from: Towger onTodayat 05:07:37Heh. How about mixing ferrite powder with rubbery paint, and marketing it as an 'EMI Resonance Damping Miracle Coating', intended to be painted all over the outside of high end audiophoolery gear. "To achieve the absolute pinnacle of listening perfection" and so on. Mix some mica flakes, crushed quartz, or just kid's sparkle powder in, to make it look special.

author: Towger
author_rank: Super Contributor
timestamp: September 23, 2017, 03:31:03 pm
content: https://www.amazon.com/gp/aw/d/B007A0RTES/ref=pd_aw_sim_sbs_201_2?ie=UTF8&psc=1&refRID=64MAHMPK7QS4G5V9HK31&dpPl=1&dpID=61OB4NoM4uLhttps://www.lessemf.com/paint.html

author: tooki
author_rank: Super Contributor
timestamp: September 23, 2017, 04:07:56 pm
content: Quote from: cdev on September 22, 2017, 06:16:22 pmcdev, I’ve mentioned your quoting difficulties to you repeatedly, offered to give you a 1-on-1 tutorial... what’s it gonna take? I still don’t understand what method you’re using to create your mangled quotes. Meanwhile, the BBcode syntax for quoting is simple, but for basic quoting you don’t even need to know it, you just click the Quote button on a post to reply with that post quoted. (You just mustn’t insert any text of your own between the quote tags, because then your text is not separated from the quoted text.)

author: cdev
author_rank: Super Contributor
timestamp: September 23, 2017, 04:53:23 pm
content: Usually I just remove whatever isn't relevant, by just leaving the words I want to respond to, unmodified.I am using the quote button. I usually try to before I hit quote, highlight the text I want to quote. In some (most) forum programs that will result in a new textarea appearing that contains just the highlighted text. That didn't work for me just now, instead I got the whole post. So, without touching the quote tags, I deleted the parts of it (like my own post) that were extraneous to what I wanted to say. Now I'm going to preview it.It looks okay, so I'm hitting "submit".Quote from: tooki onTodayat 10:07:56

author: CatalinaWOW
author_rank: Super Contributor
timestamp: September 23, 2017, 05:23:06 pm
content: Quote from: cdev on September 23, 2017, 04:53:23 pmEach forum has a style, which the members get used to and come to like. In this forum, quoted material is normally highlighted by a colored background and precedes the response. Cdev, your method doesn't produce this. There is no trick involved in following the forum style. You hit the quote button. In the resulting form you will find an initial line enclosed in square brackets which identifies the source, message number and time. Don't touch that line. The quoted message follows. It is terminated by a line with /quote enclosed by square brackets. Leave that line alone also.You remove extraneous information, highlight, bold and otherwise modify the quoted information to your hearts content within the quoted message, though it would be totally unethical to actually change content of a quote.Then put any response you have after the square bracketed terminator for the quote.This is a simple procedure and will make your responses much easier to comprehend and less annoying to members of this forum. There are more advanced techniques possible that let you quote from several messages in a single message, but no need to go there to start.I would assume that members of this forum adopt the styles of other forums when they are there. Please join us in the style of this forum.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 23, 2017, 06:40:14 pm
content: Are you using the WYSIWYG editor?(To turn it off, go to Profile, Look and Layout, "Show WYSIWYG editor on post page by default".)Tim

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 23, 2017, 06:57:51 pm
content: Quote from: cdev on September 23, 2017, 01:41:12 pmWave effects are indeed relevant in ferrite: the impedance curve of a ferrite bead depends on its shape. Longer and thin beads have kind of a shoulder at medium frequencies, then a peak at higher frequency. Wide and squat beads have one high peak.The velocity of propagation at mu=100 and k=10 (ballpark figures) is about c/32, so you get what looks like a 1/4 wave shorted stub at 300MHz with a thickness or height of only 8mm. But it's a very lossy stub, so it's not an infinite impedance at the resonant frequency, it's only a modest peak, and fairly wide (Q < 1).And, like I mentioned before, pulse applications benefit from spacing in a stack, so that when the ferrite is forced into saturation (for the case of a magnetic compressor), the rise time of the resulting shock wave is faster than if solid ferrite were used.As for wires coated with stuff, there's this oddball product:http://www.surplussales.com/Wire-Cable/Wire7.htmlCan't figure out who made it, or what specs it meets, aside from what they give there. Very weird, but indeed useful if you can't find the space to fit a regular filter module in your system.Tim

author: cdev
author_rank: Super Contributor
timestamp: September 23, 2017, 07:23:31 pm
content: I was but I turned it off. I have no problem with using "bbcode" when I need to add a link or something, simple works for me. My question is, is it still munging the previous quote?As somebody who has built web content management applications that do the round trip text thing from scratch in the (distant) past, I can say that often there are slight differences in what happens in the two different directions, which is more likely to manifest in problems the more times a content managed web page (SMF is a content management system) is edited.That's probably the problem. I often will edit a post four or five times right after its posted, and I use ad blockers, which attempt to block content from some sites that annoy me, they don't usually cause problems. Also, and this is likely part of the problem, I don't use the preview like I should, not because I don't want to, just because I forget to.But its not intentional. So I'll work on it. I promise.One thing. Having turned off the WYSIWYG editor now the rendering is slightly different. Now I see the colored box, and don't see what it appears was broken indentation.....I'll look for a good concise guide to basic, minimal BBcode and use it. I like clear clean text.I have other browsers that have no extensions whatsoever loaded on them, I can look at my posts in them.Quote from: T3sl4co1l on September 23, 2017, 06:40:14 pm

author: tooki
author_rank: Super Contributor
timestamp: September 24, 2017, 05:53:12 pm
content: Quote from: T3sl4co1l on September 23, 2017, 06:40:14 pmTim, you’re a genius! cdev, you’re absolved!I tested it, and indeed the WYSIWYG editor produces the mangled code. (What the heck is the use of a WYSIWYG editor that doesn’t produce usable output?)Quote from: cdev on September 23, 2017, 07:23:31 pmYour quote looks correct now. It’s up to you whether to add your reply above or below the quoted text, but the convention on eevblog seems to be below.