Electro-magnetic (IH) power injectors and a need to get rid of ghosts in the machine!

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Egzoset

Egzoset

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Salutations Galvatron,

If you are still battling ghosts...

Theirs, not mine as i prefer to look into my story-teller crystal ball and decide where to go next once better informed by etheral creatures...

...I still think your best bet is looking at RF amps.

So you didn't notice this previous comment i guess:

...it's still a desirable opportunity IMO to inform the audience about RMCybernetic's "CRO-SM2" alternative board where all of those aspects seem suitably addressed

There's no truly "informed decision" without telling people about other valid options and judging by what we can see it's the most valid ever encountered in my present context.

Please consider check it out because it's specifically advertized as an "Induction Heater Cicuit" to begin with. How about the Mazzilli-topology boards? Ain't so sure...

🧐

M'well, pure sine wave generation would certainly help to tame down the RF Noise but such board needs to meet demanding "stoner$"/"droÿé$" expectations difficult enough to reconcile into 1 single concept; at least analog circuits didn't have suicidal tendencies to self-destruct this much i think, something about their gates not being tied via all sorts of parasitic loops including a PSU's voltage swings perhaps...

Here's a thought...

Actually that's plain suggesting i should throw away everything i built since 2011 and start all over again at year one or so... Too bad i just don't have another opportunity "window" which became a thing of the past many years ago. These rare updates are only an attempt to give such novel ideas the fair chance it's worth for, starting with my "Bi-Energy" LAVACapsule which also been ready for some long while too, in total indifference if not denial. The fact is Egzoset may have fantasy hints but it's not only inspired by science-fiction, etc.; hence those who might think so just got misleaded along the way and now that i found 1 fair ready-made semi-DiY board/offer i'm certainly not turning my back on Induction Heating - it would be most counter-intuitive considering a most patient (decade-long...) wait IMHO. At the very least lets not judge the potential of IH driving on the basis of what we've seen so far as this only serves to block the evolution path.

Personally i yet have to see the Curie effect exploited in a beneficial manner anyway! Not that it's unrealistic, just obscured by trivial distractions at the moment. Briefly put now is no good time to loose faith, but i can understand some individuals will get bored having to delay gratification one step after the next, which is part of the DiY hobby i'm afraid!

🤫

...ever thought of ultrasonic vaporization at much lower temperature?

It's called "nebulization" and probably not useful nor even appropriate for Dry Herb "Micro-Bursting" as that later scenario relies on distributed wide-area contact-surfaces instead of sticky droplets being fractured into smaller ones. Sorry if i sound like repeating myself but i can't afford to invest in one more project with practically zero (virgin) background to follow. Nobody's omnipotent, each got a contribution of their own to offer and mine has no strings attached: simply consider duplicating the experiments for yourself, then hopefully the rest will start to fall in place. By the way my LAVACapsule concept made room for ultrasonic bowl-stirring originating from that core (i was assuming this would promote thermalization...), while these days i've been dreaming of controlled "Spot-Heating", as if "heat-shaving" the hairy legs of a large summer-end arachnoïd (without killing it)... Cruel game, long story. Please don't alert the spiders protection agency!

Good day, have fun!! ☮
 
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Egzoset

Egzoset

122
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UPDATE:

Jrg Rehrmann joretronikde   One way to drop Mazzilli diodes in Royer Gate Driving 480x360


Google's translation:

The trick of the circuit is that the diodes have been replaced by N-channel MOSFETs, which are supplied with a fixed gate voltage of e.g. 18 V.
At drain voltages below approx. 12 V, these control MOSFETs are bidirectionally conductive and connect the gates of T1 and T2 to the drain of the other MOSFET. In the zero crossing of the resonant circuit voltage, the gates of T1 and T2 can now be reloaded with low resistance and accordingly quickly. As soon as the drain voltage of T1 or T2 rises above approx. 15 V, the control MOSFETs begin to block and separate the gates from the load circuit.
Since the gate charge from T1 and T2 is now completely drawn from the load circuit, no additional auxiliary power is required. Only the gate voltage of T3 and T4 has to be made available without power, but this can easily be achieved with a resistor and a zener diode. Since T3 and T4 only have to supply the gate current from T1 and T2, they can be much smaller than these and usually do not have to be cooled. However, they have to withstand the same maximum drain-source voltage as this one.
A special feature of this circuit that must be observed is that the gate voltage of T3 and T4 must not be applied later than the operating voltage. Since the gate voltage is somewhat delayed across R1 and C1, the commissioning of the circuit as shown above could already cause problems. If the gate voltage of T3 and T4 rises too slowly while the operating voltage is already applied, T1 and T2 already get a gate voltage before T3 and T4 switch through properly in order to enable sufficient positive feedback. T1 and T2 then switch fully through without any oscillation being able to set in. The result is a short circuit in the operating voltage.
Ideally, the gate voltage of T3 and T4 is fixed and then the operating voltage is switched on if necessary. If the output of the oscillator is to be regulated, a buck converter can simply be connected upstream. The choke Dr can also take over the function of the storage choke.
In principle, it is even possible for the controller to work with a different frequency than the oscillator. In order to avoid mutual repercussions, the choke should then have a sufficiently high inductance.


-=*=-


Good day, have fun!! ☮
 
Galvatron

Galvatron

128
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Yesterday, I was troubleshooting an intermittent modulation issue on a 100 watt transceiver. As I was pressing several areas of the circuit board, my finger contacted a portion of the 20m (14.1 MHz) output filter section as it was transmitting. SSSST...OUCH! Luckily, it was a portion of the filter section and slight finger contact resulting in no physical damage. However, it was HOT! Not physically hot. the board was and remained at room temperature but the contact instantly produced a spot of heat on my finger. Whew, that could of been worse. A full contact energy delivery, even at 100 watts, can cause a nasty physical thermal injury.
Hmmm, instant heat...
 
Egzoset

Egzoset

122
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Hi there Galvatron!

Well, it's supposed to be inside a protective box, then either we throw that box away and find a replacement or we get to "service" it on the field and consequently required to open the box - which is one good motive to want those things NOT to call for troubleshooting in the 1st place...

😊

Recently it felt demotivating trying to identify affordable "eval"/"development" boards so i came to reason that there's probably lots of potential for similar incidents with autoradio stuff and hence it made me curious enough to search the web for automotive Class-D GaN-based sound systems (preferably featured with a 4th "Kelvin" pin on each power device) as i'm sure enthousiast week-end hobbyists have blown their fair share of them in the past.

Here's what i found.

Although obsolete decade-old chips as the TDA8954 may still be found in cheap items there seems to be a prolific rush of mercantile creativity around Ti's TPA3116D2, or perhaps the TDA7492P which i yet need to check, while NPX's TDA8954 already promised "fully short-circuit proof across load" in a 2 × 210 W class-D power amplifier, back in 2010! And of course mass-marketting has its advantages judging from the crazy price-tags seen on bargain retailers web sites... For example here's what one gets for his money when choosing the TPA3116-based scenarios:

Fbd slos708g 800x640
50-W stereo, 100-W mono, 4.5- to 26-V supply, analog input Class-D audio amplifier w/ SpeakerGuard™​

E.G. 4.5~26 Volts power supply range, up to 1.2 MHz Switching Frequency with external clock "sync" option (...), and then the saint-graäl of all-thumbs garage hobbyists under the form of Overvoltage, Undervoltage, Overtemperature, DC-Detect, and Short-Circuit (with Error Reporting) Integrated Self-Protection... Even with more variations on a same theme actually, like selectable "AM Avoidance" (400 KHz~1.2 MHz)!

And just when you started thinking it's a good deal for the price chances are you'll finally discover there's more ahead; an "eval" module for starters:

TPA3116D2 audio amplifier (semi-DiY)
TPA3116D2EVM Evaluation Module - User's Guide (2012)
TPA3116D2, TPA3118D2, TPA3130D2SLOS708G​
215-W, 30-W, 50-W Filter-Free Class-D Stereo Amplifier Family With AM Avoidance (2012-Apr, 2017-Dec)
Figure 37. Schematic (p26-of-48)

So my intuition says such particular chip apparently got some nice carreer so far! 😉
Mini Digital Power Amplifier Board Module with Audio Filter 100Wx2 BT5.0 Stereo Audio AMP with Volume Control Knob and Switch​

On sale for about 20 canuck bucks at the moment...

Under the circumstances i begin to think maybe this path might be worth further investigation (in a hacking perspective), after all.

Then there's the motor controllers which also deal with inductive loads. So many avenues to verify, so many options!... 🤪

Which of both routes would you personally recommend for fail-safe experimentation on stepper motors that got the rotor removed, to serve as fully-shielded IH multi-pole workcoils assembly?...

...

Please have a closer look at this particular implementation:
2261c7fb cb3a 4911 a8bb 39625e8e4e42

Wouldn't this invite for some large capacitors easy/convenient substitution, eventually?...

Imagine, i've even found bluetooth-enabled versions. 🤓

Good day, have fun!! ☮
 
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Egzoset

Egzoset

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Update:



Still observing a variety of methods all intended to address the Mazzilli cross-connected schottky diodes topology:
Many ways to address Mazzilli topology diodes in Royer Gate Driving 360x800

Each of those drawings appears to be relating a similar story, like wondering how one should deal with those diodes or even get rid of them completely.

🧐

So, there are at least 4 humans on planet earth who won't get easily impressed by dirt-cheap IH drivers built around "Mazzilli modules" clearly NOT conceived for such use to begin with. It's a cynical mirage to leave an impression it's almost magical, while the true interest in Mazzilli's topology was centered on Tesla Coil demonstrations anyway. Now lets consider JAi's warning about electromagnetic nuisance from just a 50 Watts @ 600 KHz IH driver... Quite frankly that's calling for synchronuous techniques which dirt-cheap KISS-style contests practically eliminate as a decent/viable solution; while ignoring the reward of ceasing control (by closing the retro-action loop) feels incomprehensible, especially if individuals continue to act like lemmings heading in the wrong direction even after they've been better informed relatively to their initial error - which was to follow the leader lemming no matter what. The fact remains these diodes obviously attracted attention on multiple occasions since the Mazzilli publication, around 2008 or so i think; self-sustaining oscillation the KISS-syle is a most enviable goal but it's a plain fraud to dare suggest that Mazzilli and ZVS are absolutely equivalent, then there's the pandora box waiting to get opened a bit further!

🤔

Looking at this brief succession alone i begin to have solid grounds to state it's got to mean something after all, and that's nothing trivial like the magic-thinking people appears to proclaim so promptly. Truth is one can have the benefits of Quasi-Resonance without the severe material restrictions of any Mazzilli-topology contraption costing a money-pinch fraction of 1 typical delivery bill from my local pizzeria!

Euh...

Anyway for me it's been an IH-driven month after finding out about the RMCybernetics offer, and more recently DynaVap's announcement of the Orion IH driver, although i fear there may be more Mazzilli inside... And soon the flux will feed more similar gossips (e.g. if i'm not mistaking what the gate-bias fusible about, for starters...), admit it's already been done before - just not yet.

M'well at least something kind of gets done about it!

Good day, have fun!! ☮
 
Galvatron

Galvatron

128
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Audio Amp! There you go. Simple, small, high power. As for the exciter, you can go with your astable oscillator or just a 555 timer. (KISS) A few years back, I got a pulse width modulator from RMCybernetics. Driving an old ignition coil from a Supra, made some big, LOUD sparks!!! After a while, the inductive kickback fried the 555 timer. The driver FETs were fine. So, after replacing the 555 and adding a large diode across the output for that inductive kickback, it was back to big loud sparks.
In conclusion, why re-invent the wheel?
 
Egzoset

Egzoset

122
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Hi,

Audio Amp! There you go. Simple, small, high power.

Can be found even in some local garage of the far country-sdie and comes built with self-protecting circuitry, including to deal with the average customer among other factors, i figure... While of course RMCybernetic's "CRO-SM2" may offer IH-specific features and i'm hoping for the best thinking of future releases, with microphonics and haptic (bi-dir) user-feedback for example, also in support of the DynaVap "clicker" function which can help manually limit temperature - until that's relying on the Curie effect for such crucial automation instead.

Problem with "the wheel" is that's no true "ZVS" wheel at all and this one proved broken repeatedly since at least 2008. Yet unsuspecting/vulnerable individuals continue to fall for a piss-poor bargain which ain't one after it's become clear the initial simplicity was actually calling for its fair share of agravation anyway, causing design redundancy and more, as long as people won't stop dancing at the songs of sirens...

Have a quick look at the sort of imposture going on relentlessly on Reddit's IH channel actually serving to anchor the technology into further dark ages until DynaVap & friends shall decide universality might be a nice thing too, in twenty years or so i guess. Or maybe not if an alternative manufacturer finally comes to rational senses 1st.

Ain't it peculiar enough to notice those other options don't show up in related discussions, except for a few mentions of PSU hacking as i vaguely recall, but nothing which captured my undivided attention with an obvious schematic to save my the frustration of one more "black box", which what i like about the Class-D auto-radio products with sufficient bandwidth to cover our IH-driven needs. One of the products i refered to even got its schematic published, which should facilitate hacking enourmously when it's ready to happen, but not today.

For the moment lets just watch this most inspiring interlude:

YouTube: I make an ''8 Ball'' out of solid Stainless Steel and Brass (2020-Sep-12)

🤓
 
Galvatron

Galvatron

128
43
Here's a schematic for ya, I see these come across my bench quite often for one reason or other.
It's capable of producing 100 watts @ 12VDC up to 60MHz on the HF portion.
The second amp is VHF/UHF with 50 and 35 watts respectively.
Use it as a reference on how feedback and oscillations are taken care of.
HF VHF UHF Amp
 
Egzoset

Egzoset

122
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Welcome back Galvatron,

Thanks for reminding me of tricks using smal-signal diodes. There sure was a lot of skills in those analog realizations requiring relative linear response and a low-distortion layout to match, e.g. "purity", etc... While in fact the illustrations below more closely correspond to what i got in mind for IH-driven applications. Besides of that, lets admit this Radio Amplifier's parts count simply exploded in comparison... So please have one more look on these Class-D circuits instead:
EPC9065 : High Frequency ZVS Class-D Power Amplifier

IMO we only need to give GaN a few years and the cost shall drop to irresistible levels. That one made me optimist about the future, its power input ranges from 7.5 to 12 Vdc (for control & logic support) while its associated "high-voltage" power-stage accepts as much as 80 Volts separately!

Face it, Gallium Nitride power-switching devices currently beat both the SiC + MOSFET technologies already at such select game, their low gate capacitance & charge tame down serious issues that used to call for gate "clamping" (mainly for SiC i think), etc.; in addition i suppose a few more generations may quickly succeed to each other during the next decade to come but the packaging footprints are going to be stable enough so just a handful pinout standards shall remain, hopefully (...), as with opto-couplers perhaps.

Anyway, to the risk of sounding like i'm repeating myself, a GaN version of this auto-radio chip would fill me with joy from a suddenly renewed enthousiasm; the audience might find appropriate to take notes in order to pass that fine schematic sample around too:


[ https:// www.ti.com/product/TPA3116D2 ]
[ https:// www.ti.com/ds_dgm/images/fbd_slos708g.gif ]

TPA3116D2
50-W stereo, 100-W mono, 4.5- to 26-V supply, analog input Class-D audio amplifier w/ SpeakerGuard™

Ti happens to have released an "Evaluation Module", the TPA3116D2EVM, but it sells for 148 $US, of course... If i'm not mistaking this must be its schematic below, which ain't too harsh on the eyes, nor difficult to read nor even hard to interpret globally; while labels would be practically impossible to distinguish, etc. - i know, yours was a legacy of the good old days when numerisation wasn't around in offices just yet. In fact not even this next sample could manage to get spared from any graphic polution, but we can certainly enjoy the benefits of semiconductor integration right there:
Ti TPA3116 Filter-free Class-D stereo amplifier family with AM Avoidance (2012-Apr, 2017-Dec)...PNG
TPA3116D2,TPA3118D2,TPA3130D2
SLOS708G – APRIL 2012 – REVISED DECEMBER 2017
TPA3116D2 15-W, 30-W, 50-W Filter-Free Class-D Stereo Amplifier Family With AM Avoidance (p26/48)

Check its datasheet if you still ain't done it so far:
TPA3116D2
50-W stereo, 100-W mono, 4.5- to 26-V supply, analog input Class-D audio amplifier w/ SpeakerGuard™

Actually i can foresee some fair possibility to skip capacitive input coupling and consequently exploit this chip's internal analog comparator to implement some framed control of the IH pulses, with 2 full MOSFET H-Bridges + their Gate Drivers at our disposal, which invites further IH workcoil exploration possibly using the stator assembly of refurbished 2-Phase 4-poles stepper motors; so i'd want to see adjustable 90° "quadrature" outputs following a master PLL with direct access to the master internal clock reference(s), ranging from 400 HKz to 1.2 MHz which is a true bargain!

Or do you prefer this next visual stimuli even better?

Current-Mode Class D AM Transmitters For 160, 75 and 40 Meters 375-Watt Carrier

Good day, have fun!! ☮
 
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Egzoset

Egzoset

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Ghosts in the lemons for the lemmings, e.g. those in Maxxilli-topology modules meant for Tesla Coils and sold as IH drivers without a single revision instead.
 
Egzoset

Egzoset

122
28
UPDATE



Premise for a universal 2-Phase 4-Poles IH WorkCoils Assembly:
4 Poles IH Assembly with 16 mm dia Aperture fits inside 50 sq mm PCB Layout 250x250

Using flux-concentrating material (probably as Fluxtrol's "Alphaform MF") i believe it must be possible to make it all fit within a 50 mm x 50 mm PCBoard layout in order to redirect/concentrate magnetic force fields deep inside a common horizontal plane, in a similar fashion to stepper motors:
Magnetic Flux   Open selenod coil vs Contained stepper motor 480x300

On the left that's a basic "air-core" selenoïd model, besides a stepper motor one on the right side. In a single-coil case it's clearly impossible to physically "complete" the "magnetic circuit" by joining both external poles without any flux "bending", which implies half the excitation energy is lost as parasitic "leaks" right there! In comparison , an alternate stepper motor topology collects practically all available force lines where these are most profitable, while providing magnetic paths around the assembly in order to "close" those magnetic circuits and hence also perform a fair level of self-shielding in the process - because of reduced parasitic leaks exactly.

😎

Such layout invites at least 2 scenarios i think: #1) Dual-Frequency 2 x 2-Poles optionally-independent/supperposed excitation modes; #2) Two-Phase (90 degrees shifted) compound 4-Poles driving.

Now here's my proposal for a solution to also fit this within a flat plane, e.g. horizontally and hopefully as thin as 10 mm perhaps??

Well it may come from ancient Greece but that's the best i could imagine so far:
Cardan   Universal Joint 400x360

It just needs to get aligned with its rotational axis and then compressed. AWG#12 copper wire is about 2 mm thick, if the flux-concentrating core measures 3 mm thick then that's { 2 x 2 mm } + 3 mm = 7 mm for 1 WorkCoil and its core alone, add another 3 mm thick for the magnetic circuit-closing path, which totals my preliminary 10 mm evaluation. A pair of dual-coil sets can interpenetrate each other in a complementary "X" fashion where only the center 5/8" (dia.) IH Apertures are shared, i even foresee a possibility to wrap "RF-Choking" coils around the closing paths since a flatten "C" shape would cause the 2 fields aiming for opposite directions to cancel - but i must emphasize that's only an hypothesis so far.

In any case it seems reasonable to assume 2 different frequencies can easily co-exist, separately if not simultaneously. It means both magnetic hysteris (Curie-effect) and "skin"/eddy-current types of Induction Heating would be supported by a same IH WorkCoils assembly if such intuition is ever proven correct.

Good day, have fun!! ☮
 
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Egzoset

Egzoset

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Salutations Galvatron,

If there's going to be any permanent D.C. magnetic fields then one can safely expect those to emanate from the WorkLoad itself, trying to exploit microphonics. Instead here's what i got in mind when evoking the idea of RF Choking:

Coaxial Cable RF Choking Balun 200x200

It's about A.C. signals cancelling each other inside a closed magnetic circuit, still providing a path for strong D.C., or more exactly 2 sets of them:

Coaxial Cable RF Choking Balun 200x200
Coaxial Cable RF Choking Balun 200x200
...

My 5/8" (dia.) IH aperture would correspond to a pair of aligned toroïd voids in an attempt to perform double-function, except with no obstruction in the center:

Second magnetic circuit splitting through 2 half torod paths 200x200
2nd Magnetic Circuit splits through 2 Half Torod paths   90 degrees tilt 200x200

Overall the A.C. choke signals shouldn't for the most part show up in the IH driving outputs passing through the horizontal and/or vertical external branches, with their return paths (not shown) actually folding back toward that aperture to create the equivalent of a slotted loop inside a magnetic shandwich (or cage...) requiring the insertion of my IH WorkLoad to "close" these hypothetically-separate magnetic circuits.

Simply put zero mixing ever occurs if only one of the IH paths gets activated exclusively while the other is dormant - or even better: reconfigured as an input to serve during the "listen/sample" cycles of a repeating frame where one set "kicks" the WorkLoad to "energize" it, then after shutting off power injection the other is free to monitor/capture the natural LC resonance(s), possibly even exploiting double-frequency signatures. Etc., etc. Go figure!

By "Dual-Frequency" i'm not necessarily implying 2 simultaneous carriers. To me it's more like a Bi-Modal thing but lets not exclude the more complex scenario(s) just for a lack of experimental observation!

😉

Oh, by the way. Texas Instrument is releasing an update of the auto-radio chip:
TDA7498 - 100-watt + 100-watt dual BTL class-D audio amplifier (August 2020)

Its power input range got raised to 15~36 Vdc so i gather that's more appropriate for A.C. plugged setups now, but we still get these protective features: overvoltage (OVP), undervoltage (UVP), overcurrent/short-circuit (OCP) and thermal (OTP). A "very low current consumption" mode apparently equivalent to "Deep Sleep" is available as some "Standby" function while there's also "muting", not to mention support of external synchronization.

Good day, have fun!! ☮
 
Egzoset

Egzoset

122
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M'OKay.

How about this one:
The tool box by Egzoset 2020 Oct 8 640x880

??

It may help to check a similar search as this:
[ https:// www.google.com/search?q=%22Induction+Heater%22+TPA3255&tbm=isch ]
Google Images: "Induction Heater" TPA3255

Imagine. If i ain't mistaking the apparent absence of some Induction Heat adaptation may suggest it's now possible to inject sufficient electro-magnetic energy into a susceptor for it to perform its primary duty, which is to heat when empowered using electro-magnetic Induction (via a "WorkCoil") precisely, e.g. @ 20 KHz or so i presume!...

🧐

Or... All things which flash like gold ain't necessarily made of it, so to speak. 🤔

Not to mention the "Digital Multimeter" thing...

Good day, have fun!! ☮
 
Galvatron

Galvatron

128
43
Nice and compact. Is there a schematic?
Do you have a working prototype?
 
Egzoset

Egzoset

122
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Hi there!

Nice and compact.

Ti's eval board i presume? Well i'd want it wrapped in an aluminium casing serving the double purpose of a heat-sink, then the heavy-duty binding posts need to go besides those large capacitors quite probably suitable in bass/sub-woofer applications... The remaining height is about power "chokes" which i wish could be transfered to my flux-concentrating assembly, eventually, not to mention this IH WorkCoils thing might happen to be all i need anyway, so if my intuition was correct that's compact indeed... If not here's always the RMCybernetics offer to consider.

Is there a schematic?

Oh, initially i should have posted my article-in-picture with this list of related link i've used in it:

The Tool Box... (2020-Oct-8)​
[ https:// www.reddit.com/user/Egzoset/comments/j7hwbi/the_tool_box/ ]
The tool box... (2020-Oct-8) - DELETED​
[ https:// www.reddit.com/user/Egzoset/comments/izepxg/a_most_durable_unconventional_concept/ ]
A most durable "unconventional" concept...
JAi - Company History, « Nov. 1969 Released the first Curie point pyrolyzer JHP-1. »
Curie temperatures available as a "PyroFoil" (21 of them, in degrees Celcius): 1040, 920, 764, 740, 670, 650, 590, 500, 485, 445, 423, 386, 358, 333, 315, 280, 255, 235, 220, 170, 160.​
[ https:// www.reddit.com/user/Egzoset/comments/j5v05m/egzosets_proposal_for_a_universal_800_watts/ ]
Egzoset's proposal for a Universal 800 Watts (Eddy-Curie/Dual-Band) IH WorkCoils Assembly
[ https: // www . aliexpress . com / item / 4000096268335 dot html ]
Induction heater TPA3255 300W+300W High Power Class D HIFI Digital Stereo Power Amplifier Board DC48V Digital Multimeter
Quick Look: A Generic TPA3255 Design (2017-Nov-11)​
Ti TPA3251, 175-W Stereo, 350-W Mono PurePath™ Ultra-HD Analog-Input Class-D Amplifier (2016-Oct)​
** User's Guide SLOU441, TPA3255 EVM (2016-Jul)​
TPA3116D2 - 50-W stereo, 100-W mono, 4.5- to 26-V supply, analog input Class-D audio amplifier w/ SpeakerGuard™
TPA3116D2, TPA3118D2, TPA3130D2 SLOS708G - 215-W, 30-W, 50-W Filter-Free Class-D Stereo Amplifier Family With AM Avoidance (2012-Apr, 2017-Dec)​
See Figure 37. Schematic (p26-of-48)...​
User's Guide, SLOU336B – February 2012 – Revised December 2013, TPA3116D2EVM Evaluation Module
TPA3116D2, TPA3118D2, TPA3130D2, SLOS708G – APRIL 2012 – REVISED DECEMBER 2017, TPA3116D, 215-W, 30-W, 50-W Filter-Free Class-D Stereo Amplifier Family With AM Avoidance
TDA7498, 100-watt + 100-watt dual BTL class-D audio amplifier (2020-Aug)​
Ti TPA3255, 175-W Stereo, 350-W Mono PurePath™ Ultra-HD Analog-Input Class-D Amplifier (2016-Oct)​
ST Micro MASTERGAN1, High power density half-bridge high voltage driver with two 650V enhancement mode GaN HEMT

Do you have a working prototype?

"Plan-A" as i explained remains in its preliminary design phase, while "Plan-B" has been thoroughly demonstrated and since it's based on a Bi-Energy Hybrid Core i'm expecting no significant difficulties in the replacement of clean-burning butane with IH driving, except i may find necessary to restrict metal parts to the susceptor itself should my "spot-heating" IH strategy still prove insufficient, but i'm resoltutely optimistic at the moment.

Thank you NBSDSailor for the interlude, now here's some of my own about a "Prototyping Platform" of which the internal layout stablised a couple years ago i think:
Egzosets 2018 LAVA Hybrid Core   Where to Cut 640x480
Heat Decoupling Pads of 125 mm dia x 1 mm Metal Disc with 17 53 Holes 2019 Jul 31 400x40
Egzosets 17 Holes Metal Disc Lava 10 mm thick x 1246 mm dia 2017 May 14 400x300
Egzosets Cust VG Pipe   Dual Flame Alu Top 2018 Dec 19 400x400
Egzosets Cust VG Pipe   Internal Classic Handle Routing 2019 Jun 1 530x480
Egzo Cust VG Classic   Int Thumb PinHole Route   Labelled 2019 Jun 1 530x390
Left Hand Manual Thumb Control of On Top Core PinHole 300x400
Egzosets 6th Year Duo of Cust VG Pipes 2019 Mar 7 800x325
Egzosets 6th Year Ed of Cust VG Pipe got On Top Core PH 2019 Mar 17 400x400
Egzosets Cust VG Pipe   Minion 4 20 Ed 2019 Apr 13 640x480
Egzosets Cust VG Pipe   Only Dan Steinberg can do it 2019 May 8 480x360
Egzosets Cust VG Pipes   2019 Summer Solstice Ed 640x480

Good day, have fun!! ☮
 
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