Unwinding a tiny 6kV xenon trigger transformer

[@crackedemerald4930]

Transformers in my head are the gearboxes of the electronic realm

[@hobbified]

Yup. Turns low torque high speed into high torque low speed, or the other way around.

[@AnnaVannieuwenhuyse]

@@hobbified looks like magic, takes a lot of knowledge before starting, and insanely powerful skill once you master it. Smells like gearbox, looks like gearbox, can sound like gearbox. Yup, it's a gearbox.

[@mimimi9170]

or leverage :)

[@absalomdraconis]

@@mimimi9170 : Give me a high enough windings ratio, and a ground to reference off of, and I will move the very earth!

[@mimimi9170]

@@absalomdraconis ahaha you're god damn right Archimedes

[@twocvbloke]

Examining transformers is a good weekend project, it helps to unwind.......... :P I'll get my coat!!!

[@userou-ig1ze]

if you're not at dad yet, your jokes shall henceforth quality you as one ~the internets

[@chrishartley1210]

The voltage between layers is actually about 1320V at one end and 0V at the other end where the winding reverses direction. The 660V you calculated is the average between layers.

[@danwhite3224]

I remember buying one of these from Maplin (among other things) as a young teen just because I saw it was a "6kV transformer" and I wanted to make HV arcs with it, but I had no idea how it worked and I just ended up blowing it up

[@itemushmush]

RIP Maplin :(

[@GoldSrc_]

As a kid, I used to plug LEDs straight into the mains thinking that they would be way brighter, turns out they just crack internally and get dark lol.

[@ianhosier4042]

@@GoldSrc_ it's how you make a black LED

[@wingerrrrrrrrr]

@@ianhosier4042 That's a dark emitting diode, commonly called DED.

[@ianhosier4042]

@@wingerrrrrrrrr don't you mean a DEAD?

[@jrmcferren]

Seeing those rounded ends and the wax reminds me of the old wax-paper capacitors you find in old valve radios. Of course, since these don't have the paper being used as a dielectric, I would hope that these wouldn't break down so easily unless the wax melts or cracks and lets moisture in.

[@wimwiddershins]

This reminds me that I have a few of those around Ive been meaning to tinker with. Tingley mischief ensues.

[@johnrehwinkel7241]

The data sheet gives the wire sizes, which happily match your measurements.

[@bigclivedotcom]

I didn't spot that.

[@PatrickLeeUS]

Only Clive could get away with calling wax a "weasely creep."

[@georgeblair7129]

wonder how that compares to whatever they used in the old kodak disposable cameras. Those gave quite the shock if you touched the board in the right places.

[@ICountFrom0]

Loved taking those apart to tinker with.

[@gavinsauer1608]

@@ICountFrom0 Same! So much potential for projects. I got a very good shock and a burn on my thumb the first time I opened one lol.

[@redoverdrivetheunstoppable4637]

that's the 350V electrolytic capacitor... not too long ago i opened my compact camera, got shocked, destroyed the flash circuit, it doesn't flash anymore, i salvaged the tube, the 350V cap, the transformer and also a SOP-8 IGBT that apparently cuts the flash duration to save cap charge and batteries

[@arthurmoore9488]

Ahh, memories. Back when you could bring pocket knives on airplanes. I, as a kid amused myself on the flight back from a vacation by tearing one of those apart. It was quite shocking. :D

[@chrismueller8861]

You would be a great teacher. Your proficiency in terms of electronics and electrical engineering and analyzing even highly complicated schematics is just outstanding. Keep it up Sir

[@gyrgrls]

I like to watch these videos whenever I need to unwind.

[@snowdaysrule]

Best piece of advice I ever received as a kid (that I listened to) was to "go down to your local drug store and ask if you can have some of the processed disposable cameras." 20 years later and I still have the box of around 100 pcb's from my haul! Each board has a trigger transformer and flash tube and it was so cool to see all the variations in parts and design from the major manufacturers.

[@TechGorilla1987]

@4:32 - I'm happy to say that I have been here to witness most of those apprentice marks visible on this bench.

[@matthewgriffin4761]

I remember making a Velleman Stroboscope kit that used one of these. Great video Clive.

[@picobyte]

Those trigger transformers are exactly the same as the ones from camera flashers I took apart as a kid. Some designs are just so good they're final.

[@tiggywinkle1000]

Excellent and very informative video, thank you. I still have a few of these little Tx's lying around in my workshop. These ones were made by RadioShack. Back in the '70's in my days as a club DJ big strobes were practically unobtainable, and ones that were triggered by the bass beat in a song did not exist at all, outside of Hawkwind's collection of mighty 4 channel Rainbow Strobes. I found a bog standard battery driven little 'photoflash' circuit, and beefed it up to work direct-on-line (no isolation Tx - would have made it too heavy) from the 240V mains - the upgraded PSU developed well over 480V peak to peak to a set of 3 massive, 5 Joules each, Xenon strobe tubes soldered into an Octal valve plug and their trigger poles commoned. The power to drive them was stored in a bank of 32uF 600VDC PF capacitors, with the safety resistors taken out (Health and safety? - Oh right - it's the 1970's). The trigger cct. was built using a 741 op-amp in an active low-pass filter that took a signal from the LS cabinet and the o/p sent via an isolating pulse Tx to a UJT that fed the trigger Tx. The reflector was made from an old silvered glass footlight reflector salvaged from an Edwardian theatre demolition - it was just over a foot across. The effect was absolutely awesome. Dancers appeared to be in 'stop motion' as the beat from the disco track matched their rhythm. I got paid serious money hiring it out to other club DJ's, also. Great times !

[@eiv-gaming]

Here was me waiting on Clive making one have some magic smoke. Blue balled by the big man.

[@notsonominal]

he'll blue smoke you before long, i'm sure!

[@blkmgk16]

I just took apart a few old disposable cameras yesterday, this is great thanks Clive!

[@berndeckenfels]

“For other high voltage purposes” Ozone!

[@tonythemadbrit9479]

Nuclear device initiator :-)

[@prakharmishra3000]

Electric chair :)

[@mkill73]

@@prakharmishra3000 Its not high voltage, its high current. Current kills not voltage!

[@prakharmishra3000]

@@mkill73 oh no mehdi will be really mad

[@SuperAWaC]

Flash lamp pumped ruby pulse laser ozone generator

[@johnmcclain3887]

you do such careful research and fine work, I enjoy watching you tear things apart, and describing in fine detail, often that I've never heard of before. You do beautiful circuits and symbols, very easy to read understand. Thanks, I have to go look these up now.

[@johnmcclain3887]

I've worked in electronics for almost sixty years, have had to focus on this insane clown act that I've seen as a bioweapons effort, quite successful from the start, with two decades a Marine, avionics tech, and with experience with such bio-warfare, and this has been the flip side of the coin, I know what they/'ve done, how, why, had multiple sclerosis, "gulf war disease" since my "classified, experimental anthrax vaccine", studied it thirty years, and I get to relax, think about not insane carnivorous clown con games, and see tiny things that didn't exist when I was delving into electronics daily. I've worked on "large scale integrated circuits", when they were tens of thousands each, going inside, removing a bad component, replacing it, or delving ten or twelve layers down on a multi-layered board, to fix a broken or burnt run, through a microscope, so watching you do this is great fun, escape from the insane political game, and I am re-united with "fun electronics" I began with, things like home built radios, crystal radios, hand made motors, and the like. I really enjoy the skill you have with "electronics knowledge, experience with circuitry, and your fine skill at teasing out the cause of the failure, or the heart of the interesting circuit, and your observations of why they chose a design, or why they shouldn't have done so. Sanity is a fragile thing, and we all need to live outside of fear. I've found some most interesting people, all over the world, all over the internet, sharing, as never before in my life, it's the best reason to fight to live, free.

[@Miata822]

Amazingly compact. I can imagine a few obvious little projects that are best left undone.

[@GNARGNARHEAD]

oh that was super informative, that layered voltage difference explanation was invaluable, thanks so much

[@dwaynewladyka577]

A sibling of mine got an electronic barbeque lighter once. It used a 9 volt battery. It had a 1000 MF, 16 volt electrolytic capacitor, a small transformer in it, and a switch. He put it into a small project box. It put out quite a jolt. It was a miniature version of a car ignition coil. If I recall, I think I have seen the transformer you have on some type of photo flash circuit. Cheers!

[@tebbi67]

I’ve taken such transformers apart many times . . . . . but I misunderstood the actual function. Now I'm a lot smarter. Thanks for that. And for the Vid.

[@Lazy_Tim]

Amazing that they can make them so small. I would love to see the production process.

[@glasslinger]

An assembly line of elves!

[@nigel-matthews]

@@Willam_J 😂

[@jdog987]

Oh how I like it when these lesser known schematic symbols come up, such as for the sidac, because so do the (lesser known) memories come to me from early college. It must have been Analog204 or something where we were getting into AC stuff from DC. Our Prof said something like "Notice how the symbol doesn't resemble a diode so much as it does a big Z.. that's because you might receive a big Zap into your fingers or DMM if you go across it, and you'll find your meter doesn't turn on anymore." It was one of those moments you knew that was spoken from experience, and he didn't have to say it.

[@davescreations7793]

I enjoy watching your videos Immensely because you explain and show the correct wording for whatever you work on thank you very much

[@jayare1933]

THE VOLTAGE OF THE BEAST!

[@PropGuru702]

Wow.. thanks a bunch Clive. Been working on a very small xenon based flash circuit and this has helped a bunch. Cheers!

[@lasersbee]

Would like to see the Sidac triggered circuit work..

[@bigclivedotcom]

I'll be making one.

[@notsonominal]

That was transformative; on many levels or layers if you like..

[@gordonirving24]

Sidac, you had made that up until I checked!

[@BRUXXUS]

Oh wow, with that sidac and one of these coils you could probably get some really interesting high frequency, high voltage fun from very few components! I kinda want to play with these things now. 🤩

[@fir3w4lk3r]

If I am not mistaken the transformer ratio is valid for sinusoidal current. Pulsing the transformer may produce much higher voltages.

[@bigclivedotcom]

It's designed for pulsed use.

[@nrcha]

I should buy these. Perfect when someone wants to unwind after a long day.

[@redoverdrivetheunstoppable4637]

winding is more relaxing

[@gregbell2710]

I love high voltage transformers and little things so this gets a 👍from me :)

[@salfordjc]

back in the day l have had a few zaps off the old flash guns whilst taking them off the camera without discharging the flash first

[@anthonykennedy6758]

I missed everything after you drew that amazing lightning bolt…

[@joehopfield]

Wax is also flexible/self-healing (since the coils expand while carrying current). US utility pole transformers where I live at least used to be oil filled.

[@jayreiter268]

Clive I worked with strobes quite sometime ago. The trigger circuit at that time was a voltage divider and a diac to fire the SCR. As a note I used the winding from an audio out TX to replace a shorted trigger TX

[@michaelmoorrees3585]

Use to use these trigger transformers in strobe circuits all the time. Radio Shack use to sell both the transformers and xenon strobe tubes, back in the old days. You use to supply ~300V, that charged up a special electrolytic, that could handle the high current pulse, when discharged. These have been replaced by really bright LEDs, in cameras. Even old disposable film cameras, had xenon strobes built into them.

[@bigclivedotcom]

And they sold the big fat flash capacitors.

[@EricWillis77]

I like taking stuff to bits but wow the patience that had to take to do that so we don’t have to. ⚡️🇺🇸⚡️🏴󠁧󠁢󠁳󠁣󠁴󠁿⚡️💯👍👍👍

[@kwinterburn]

Just a suggestion get a disposable film camera, single AA cell HV inverter and a flash tube and trigger for a few pounds

[@dwaynewladyka577]

I agree. Once, when I was young, at a garage/yard sale, I bought a toy gun. It had a photo flash type circuit inside, but didn't have the electrolytic high voltage capacitor that a regular photo flash circuit had. It still had very small transformers, and a mini flash tube. It was pretty neat.

[@Mr.BrownsBasement]

You may be able to have even more fun if you can find a miniature Flyback transformer. You can get more than just a pulse (or rapid train of pulses). I found one of those miniature flyback transformers in a plasma lamp. Really cool.

[@glasslinger]

The coils I got hold of were not so friendly! They had potted them with epoxy! I got an idea of how many turns by taking the coil on the belt sander and sanding off the coil to half gone giving a complete cross section. I was able to use a glass to see how many turns on a layer and how many layers. No chance whatsoever to reuse them like the wax potted coils you got.

[@bigclivedotcom]

If they're the little black box type they are definitely more reliable than the open ones and have the advantage of a higher voltage rating. You could wind your own custom primary on the outside of one.

[@tikaanipippin]

Love your kinky-pinky calculator!

[@toddhodgson2130]

Use that in a solar garden light to turn it into a mini bug zapper???

[@Cornz38]

My lord. I remember having to use these for the Velleman strobe lights. I copied the PCB but couldn't get the actual transformer and i had to work out the wiring. Oh the halycon days of Maplin electronics and Velleman kits.

[@Graham_Rule]

That took me back to unwinding a transformer and getting waxy stuff everywhere. I'd burned out the power supply for my train set by holding the reset button down and wax had leaked out of the transformer (and then presumably shorted). I was amazed to see just how finely the wires were wound. But, come to think of it, no more finely that the spools of thread on my grandmother's ancient sewing machine.

[@Roy_Tellason]

A source for some interesting parts along these lines is the electronics you find in disposable cameras that are equipped with flash. If anybody is still using those, what with everybody having a camera in their phone these days. The ones I've seen have a little transformer of E-I construction IIRC.

[@martinesimmonds5590]

Hi BIG CLIVE. It would be great if you could make videos on electrical conundrums. Things that do not make sense but Electricians do it anyway. A surprise video every now and again would be great. Thank You Big Boss Clive.

[@johnsenchak1428]

You could have a 555 timer pulse t a transistor which then triggers the thy-resister. The wax is used to insulate the primary and secondary in the case of hi-pot testing at the factory

[@mvdbroek166]

I think Wax is used as it is indeed thin when hot, so penetrates deep but also as it is “selfhealing”

[@dalenassar9152]

I need just such a trigger xfmr...but with the coils isolated (4-wire). After watching your video, it seems an easy task to simply isolate the pri. and sec. windings simply by cutting a wire and re-assembling...perhaps with some isolation and maybe a replacement primary. Doable???

[@bigclivedotcom]

Tricky. You might be able to find a potted version that has all four connections separate.

[@kevgermany]

That's really interesting, thanks. Just wondering how this applies to flash guns where they vary the flash length to very light output. And going further, Xenon headlamps on cars.

[@qcsupport2594]

I dig the zoomed-in datasheet.

[@piconano]

Excellent. I love high voltage as much as I love LEDs.

[@mohinderkaur6671]

Triggered spark gaps - may also work with this coil.

[@lambda7652]

Can you try to trigger it with a neon tube?

[@flipschwipp6572]

I think I saw some SMD flash trigger transformers in DSLR cameras which only were like 3mmx8mm. But maybe they are only 1-2kV output

[@kyleshady9777]

If you crack open an HID lamp ignitor, like for HQI, it contains one of those plus a capacitor.

[@benwinkel]

I love the Kinky Pal-culator.

[@raphaelschneider7852]

I always thought that there was magnesium in these Tubes. Xenon makes so much more sense Thank you!

[@robertlapointe4093]

The old single-shot flash-bulbs used magnesium wool in an oxygen atmosphere. The trigger pulse (not sure what voltage) just ignited the magnesium, which burned rapidly, consuming the oxygen in the bulb and sometimes shattering the bulb with an audible pop. The bulbs were usually plastic coated so they didn't make shrapnel if the glass envelope shattered. Wikipedia has a page on flash photography covering everything from the really old pans of magnesium flash powder up to high current flash LEDs: en.wikipedia.org/wiki/Flash_(photography)#Flashbulbs.

[@Scrogan]

I’m looking into using these for resonantly driving EL wire. Trying to use it as an inductive element in an LC low-pass filter doesn’t really work, at least not while its secondary is in parallel with the capacitive load. The whole system acts like a capacitive load to my half-bridge, so I’d need to use another inductor. At the moment I’m testing just using 12V with a single inductor and hoping the voltage floats up high enough with the high-Q of the system, if not I might have to use a switching converter to get a higher voltage for my half-bridge driver’s floating high-side. Using a transformer + inductor is still on the table, but getting the feedback loop working is proving somewhat difficult in my simulations.

[@bigclivedotcom]

EL wire runs at around 100V. Much higher and it could get damaged.

[@Scrogan]

@@bigclivedotcom Yes but I’m trying to drive it as efficiently as possible off a 3.3-4.2V lipo. I find the standard flyback designs have a lot of coil whine and eat through batteries, hence why I’m looking at inverter-style topologies. I doubt I’d get much above 100V from the high-Q of an LC oscillator anyhow.

[@mohamadtarmuzi924]

Thanks for your explanation

[@Abihef]

Thats one impressive spec of copper and plastic😮

[@jamesbrown4092]

Looking forward to the experiments with super happy fun times spicy voltages.

[@nigelworwood8530]

Only you could unwind a transformer and have us sit there bobin' along transfixed.

[@tluangaparte4692]

sir ,how much copper wire guide?

[@28YorkshireRose12]

Ooh..... I detect a discreet taser coming up, or some elec-trick shockery gadget!

[@helmuthschultes9243]

The fine inner winding could be 0.07mm wire, which was typical in automotive ignition coils that were oil or tar filled, and similar in the modern transformer ignition coils. So readily available in volume. Though the modern coil on spark plug do go even finer. The fine wire is more difficult to source and gets more expensive, to point of rediculous for significant lengths, no longer based on copper volume sold. I also have some 0.01 and 0.02mm wire both enamel insulated and bare copper, used on BGA connection repairs ( ie mobile phones) That is sold by meter rolls. So where required even such fine wire is available to extreme fine limits. 0.01mm is so fine it is almost invisible and easily torn, just running it over your finger hardly feeling tension. Definitely tweezer and microscope work.

[@martinmoeller9186]

Another source of very fine wire is earphone cables, at least the better quality ones. They are multistrand very fine wire, not sure exact size but small enough to do a mod on a deep inner layer of an 18 layer pcb. Picked up a differential pair that was ~4 mil trace maybe 3 mil spacing. That was definitely microscope work where you work between heartbeats, glad I only had to do 1 to prove the fix.

[@olipito]

May we see one at work?

[@brencrun5068]

Flip the primary common and capacitor connections and the primary voltage will then add to the secondary giving a few more volts out. Also, the Xenon tube once triggered only ceases when the CURRENT, not the voltage falls too low. Lastly, it's likely the wax is a silicone based product, high dielectric strength, excellent penetrating capability and water repellent.

[@Reactor89]

What happens when these transformers overheat? Given the wax.

[@bigclivedotcom]

In the event of miswiring the trigger and power connections on a string tube, the wax melts and the transformer goes open circuit.

[@Reactor89]

@@bigclivedotcom Does it first short out and then the wires act as fuse that goes open circuit? Thanks for the reply.

[@JedrzejP]

4:30 one and only short glimpse of the "Structure" diagram not obscured by anything

[@sparkyprojects]

Also camera flash Best way to find the size of small wire is to wrap 10 turns or so, then measure that ;)

[@dlarge6502]

Now I know what to use a thyristor for!

[@primateinterfacetechnologi6220]

for some reason, tiny things are fascinating... especially high voltage tiny things. the minuscule motors that vibrate cell phones are rather exciting... but those little rascals you have there are hard to top. I'm thinking maybe a wearable mosquito zapper... that would be most exciting. especially if one forgets that it is there and tries to adjust ones' hat. I have some equivalent Transformers, maybe I should try and build one... or maybe I shouldn't. peace be upon you, sir.

[@theskett]

"Wearable mosquito zapper" -- ingenious. I was just in Poundland (but forgot to check whether they had £1 zappers), then spent a few minutes sitting on a park bench (beautiful summer's day...) and got molested by hundreds of small flies. Sparks and carnage would have saved me a lotta hand-waving :-)

[@primateinterfacetechnologi6220]

@@theskett yes yes: imagine the endorphins one would get upon sensing a minuscule Menace approach... only to be quickly and colorfully "neutralized"... from dust, back into dust. probably would be a gift of unending excitement for someone working in a mosquito and vector control program too. hmm....... there are so many design considerations. so many. hey, peace and rock on from across the pond...

[@allthegearnoidea6752]

Is this not a fly back transformer so the transformer ratio doesn’t really explain the voltage magnification ?

[@bigclivedotcom]

It's designed to be pulse driven.

[@allthegearnoidea6752]

@@bigclivedotcom well yes fly back transformers are pulse driven hence the ferrite material rather than a iron core material. Sadly I don’t remember the math but rate of change is related to the output voltage and involves some differentiation in the mix. Thanks for the videos and fun a big fan here. Thanks Clive.

[@ssupertutorial]

Sorry to disturb but can you link the place you got that super small transformer pls i was unable to find it ;)

[@bigclivedotcom]

www.aliexpress.com/item/33038629163.html

[@ssupertutorial]

@@bigclivedotcom thanks a lot 😉 just putted in my shippingcart

[@ejonesss]

what happens if you wire a fluorescent tube in place of the xenon tube?

[@bigclivedotcom]

It would probably make it light, but could damage the electrodes by using in cold cathode mode.

[@ejonesss]

@@bigclivedotcom i was thinking if you could explode the tube because it was not made to handle that kind of current. while the bulbs are not too expensive you can experiment with junkers that still work but are being replaced due to epilepsy triggering threat. hospitals and many rehab places will replace the bulbs before they start to flicker so you can get a junker from them. often when they fail they fail where the filaments burn out so they cant strike normally so they need a high voltage to strike them.

[@electroumit]

Thank you. You are awesome.

[@Farm_fab]

Clive, back in the 80's when I was in electronics school, I had a camera flash with a xenon tube, and we took the flash head and ran 250 volts through it, and it sorta lit, but not like a reading lamp. Another bit of fun I had was with a g defective halogen tube from a copier. I rigged a high output transformer to the inputs, and got a small great spark through the bulb since the filament was not intact. Just curious if you have any knowledge on these light sources?

[@joseph8208]

Is this something which can be used with ac and dc?

[@bigclivedotcom]

These transformers can only be used in pulse mode.

[@carlyonbay45]

can you connect LEDs to one ?

[@bigclivedotcom]

No real point.

[@gerrymarquez4047]

Hi, How many turns in Secondary coil?

[@bigclivedotcom]

480 on the datasheet.

[@gerrymarquez4047]

Oh, ok Thank you so much.

[@Nuts-Bolts]

Wonder if winding a trigger wire round an ordinary florescent light tube would get it to strike, without the need for a choke?

[@janami-dharmam]

better to paste it along the length

[@eDoc2020]

Yes. Putting high voltage AC near a fluorescent tube makes it glow.

[@orac229]

Is it possible to put this next to an AC cable and power something? like the USB phone charging coil stuff. What I want is a light that I can just put near an AC power cable and have it light without batteries or direct connection to a power source?

[@bigclivedotcom]

The coupling isn't enough to do that.

[@The_Petrichor]

Instead of the zidac or the tharistor, could you use a zener?

[@bigclivedotcom]

No. A zener would just start conducting slowly at its voltage. A sidac suddenly turns on and dumps current.

[@TriunfoGim]

Thanks you Sir.

[@TheUnknownCatWarrior]

I know one thing: the Chinese manufacturers use ultra thin copper wire...

[@girrrrrrr2]

Is this the same kinda transformer that was in that violet wand/hair folicule stimulator that you tore down a while back? Just wondering mostly.

[@bigclivedotcom]

Similar but larger scale.

[@girrrrrrr2]

@@bigclivedotcom Interesting thats what i thought thank you!

[@tjsynkral]

If you put 2 of them in series will you get 140kV? Or, more interestingly, what will the failure look like.

[@bigclivedotcom]

It would flash over undramatically.

[@janami-dharmam]

the secondaries are not isolated; so that won't work

[@eDoc2020]

If you wire them in opposite polarities with the center tap near ground it would probably work.

[@chrisw1462]

I was told (many years ago) the wax was to prevent moisture infiltration which would change the inductance value, which might cause it to fail to ignite the lamp or arc over. Never understood how that was supposed to work...

[@bigclivedotcom]

It could also avoid areas for corona to form.

[@igrim4777]

There is a trivial lowering in inductance due to water having about 8 parts in 1 million worse relative permeability, but as I understand it the cause is primarily due to different dielectric properties. Water will lower the self resonant frequency of your inductor. You probably need to know a little physics or transmission theory to understand why, let's just say that electromagnetic signals propagate at different phase velocities in different media. While inductors may be designed to have (approximately) constant inductance over their intended operating frequency, the presence of water will lower the phase velocity at which the electromagnetic field propagates, lowering the self resonant frequency of the inductor and increasing its inductance in the intended operating range. For comparison, the dielectric constant of air is 1, paraffin wax is about 2, room temperature water is 80. Wax will change the inductance but far less than water.

[@janami-dharmam]

wax provides great insulation, particularly near the ends. I also seals pinholes because it has a low melting point. Inductance values are not critical because the output voltage should be high and oscillating. Just high voltage outside the tube has no effect - you need ac to couple to the gas inside.

[@mikabuck9866]

Love that calculator. 😁

[@jmir33]

You don't suppose that they use wax to help manage the heat in the coils, do you? Aside from being fairly cheap, easy to work with and readily available, that's the only reason I can suspect wax would be used.

[@igrim4777]

Wax is an insulator so it will only manage heat if your idea of managing heat is retaining heat, the problem being that the more heat it "manages" the closer it gets to melting and the less managing it will be doing. It's cheap, it insulates, it will flow, infiltrate and conform to the wire and restrain it when it freezes reducing magnetostriction and acoustic noise.

[@bigclivedotcom]

These coils dont really get hot in normal operation.

[@psirvent8]

For the resin potting I remember your web page about the stun gun and I wonder if it would be possible to vacuum pot a small transformer or inductor or anything else by simply pouring epoxy resin and drawing a vacuum with... a vacuum pump ? I do happen to have a manual one for bleeding my car's brakes but you may also now about electric ones that are primarily used by refrigeration technicians/engineers and also for vacuum chambers. What about putting the whole assembly to be potted inside a vacuum chamber too ? Or in other worlds what is the "specialised vaccum potting equipment" that you mention on your web page ? (I do remember old neon sign transformers being filled with tar instead of resin too) But why is wax outdated ? Is resin more reliable or something ?

[@bigclivedotcom]

The resin vacuum units usually have a chamber with clear lid and refrigeration style pump.

[@PocketOperatorGuy]

It's a nice hackable gem! Great video!

[@moodyga40]

if you put the cap in series it should limit the current as well

[@lvomotor]

kink palculator? sounds pinky.