Plan-A, IH-driven DiY ideas for DynaVap VapCap enthousiasts.

[Egzoset]

UPDATE:  i had a somewhat fresh, if not slightly unexpected, euh...  "surprise" just recently:

 

(some musical Tesla Coil e-Bay offer...)

 

They've arrived and no hints ever seemed to reach me until yesterday!

 

Furthermore:

 

 

And there's even been a "CRO-SM2" revision since then:

 

 

So...  What was i saying all along ??  ... 

 

It's already been done before, just not yet!!

 

 

Edited August 25, 2020 by Egzoset
Read-proofing.

[blackpoolbouncer]

Forgive me, I may be way off the mark. But could you not use the electronics from hand held induction guns that already exist? 

Like an induction bolt remover? Surely that has a similar board fitted inside an already tiny hand held device? 

 

You can purchase induction boards pretty readily even off eBay 21 quid gets you a set up to heat a 40mm crucible. 

 

I don't know if it's any good to you or not and despite being rude to me in the past I thought It might be helpful for you. That's if you haven't blocked me as you said you were going to. If it's not no worries. 

 

Good luck with the project. Interesting even if much of it is over my head.

 

 

 

[Egzoset]

Salutations BlackPoolBouncer,

 

6 hours ago, blackpoolbouncer said:

...I may be way off...  ...  ...despite being rude to me in the past...  ...  ...if you haven't blocked me as you said you were going to.

 

I have and the chances are i got in a bad mood because of similar out-of-band noise as observed today just when the topic should have went a radically different direction.  That's called topic derailment and that's motive enough to raise a flag, nothing personal from my part:  e.g. simply adjust your actions to observe a corresponding reaction.

 

6 hours ago, blackpoolbouncer said:

...could you not use the electronics from hand held induction guns that already exist?

 

Then why not leave it alone and just use it "as is"?

 

6 hours ago, blackpoolbouncer said:

Like an induction bolt remover?

 

I wrote that too, well over 5 years ago at the very least.  M'yeah, but unless it's self-regulating via the Curie effect that might cause over-heating issues, especially when relying on human intervention coupled to a bimetal (mechanical thermostat-like) clicker to close such temperature-regulation loop, e.g. manually...  And right now it seems to me the favourite "tuned" DV VC frequency is going up rather than down, away from this precious Curie effect anyway!  As a matter of fact JAi patented their IH Curie Pyrolyzer in 1969 as i vaguely recall (despite having to reapeat myself so many times);  sorry if i seem brutal with such "fresh" news!  Chance are in reality you may already have the option to buy all 21 temperature-specific PyroFoils from JAi and try them all until one fits your future IH-driven application.  Which is one thing i'd like to experiment with very much myself, but that's only me saying so please don't take my word for it, put those statements to test for yourself and feel most welcome to share new perspectives with our "communality", eventually!

 

 

6 hours ago, blackpoolbouncer said:

Surely that has a similar board fitted inside an already tiny hand held device?

 

Nope, actually i'm convinced a suitable strategy for AC-operated scenarios is NOT to start with a low-voltage power source exactly.  It's quite probably similar to kitchen IH cookers, dental wax hot-knifes and hairstyle IH-driven hot-rollers, not pretending i've identified all of the 3rd-party ready-made commercially-available products just yet.  With high-voltage readily accessible it's becoming practical to benefit from alternative iGBT or even SiC/GaN technologies, while a portable vaporist IH device running on 2 or 3 batteries poses its own designer challenges and not necessarily in a same familiar order.  For example although Gate Driving only represents a fraction of the energy budget for a table application it's some other story once we realize that Gate Driving easily measures in the hundred milli-Watt range, hence calling for components with "margins" often totalizing 2 to 5 Watts each (mainly to prevent accelerated aging and catastrophic failure), especially if that's about a Mazilli topology i guess.  The good news being that high-frequency gate-driving is easier to attain at low-voltage, which is why computers started having power supplies below the standard 5 Volts in Y2K days...  One major technical challenge to solve is Gate Capacitance and the less voltage it takes to flip a power switch state the less current gets wasted as internal heat to fight such electric inertia, essentially.  And it turns out recently i was reading about the Mazzilli e-Bay modules being equiped with MOSFETs characterized by gate capacitance past 1 nano-Farad, while the present trend is to rise in frequency toward 100 KHz and beyond, because that must be an easy short-cut compared to dealing with Curie alloys.

 

6 hours ago, blackpoolbouncer said:

I don't know if it's any good to you or not...

 

You see that's the sort of behaviour which causes me to raise the [ IGNORE ] flag after perceiving a persistent pattern:  you paid ZERO attention to the product's innovative claims and this is what should be on topic right now.  Stop re-focussing my dedicated thread and we'll be better acquainted with each other, continue to talk to Egzoset about Egzoset and thou shall remain in the purgatory corner for eternity, or until the server is definitively swtiched off - or if you use one of your many different incognito identities.  Which is all noise automatically raising a red flag.  In the film Matrix the french man called that causality & effect i think.

 

Good day, have fun!! 

Edited August 25, 2020 by Egzoset
Read-proofing.

[Hippie on hill]

Here's the next Dynavap Dynatec offering (that I don't think I should be posting but the cat's out the bag now so ....) 

 

 

 

1000 mAh battery

11cm x 6cm x 3.5cm

150g

USB-C

5-7 seconds to click

10 sec. safety shutoff

 

Will be about $200 I believe 

[pothead11]

$200 dollars is to rich for me but it does look nice. If I could afford it I'd probably buy one .

 

Edited August 28, 2020 by pothead11

[Hippie on hill]

Yeah it's smaller than the current crop but it's a bit pricey 

I really thought we'd see a few more pocketable triple 18350 and dual 18650 battery sled builds using the cheap board by now, and was expecting some form of power adjustment (and hoping for temp control) in the next gen of IHs 

 

 

[Egzoset]

Salutations,

 

8 hours ago, Hippie on hill said:

...I don't think I should be posting...

 

There won't be any protest from Egzoset over communicating information which is most relevant in this present dedicated thread.

 

7 hours ago, pothead11 said:

$200 dollars is too rich for me...

 

What we really need to know is what's that 200 $ buying exactly and hence i'm no fan of vague fanboy-supported "black boxes" nor mystical proprietary code, etc.  Clear schematics feel much more convincing to me...

 

5 hours ago, Hippie on hill said:

I really thought we'd see a few more pocketable triple 18350 and dual 18650 battery sled builds using the cheap board by now, and was expecting some form of power adjustment (and hoping for temp control) in the next gen of IHs

 

Patience.  The next breakthrough may come from the lower RDS(On)of Gallium Nitride power-switching devices combined to their extra-low Gate-related parasitic-capacitance(s), and it's good news enough - especially if we consider this implies additional strategic gains for a battery-operated portable-autonomy context.

 

 

5 hours ago, Hippie on hill said:

...was expecting some form of power adjustment (and hoping for temp control) in the next gen...

 

The Mazzilli-topology boards exclude this possibility by design, not to mention i'd personally want some fair/updated rationalization pourred into the blueprints.  For example to break an IH session into steps or phases like this:

 

• Power-up (including early "Shoot-Through"/"Interlock" management)
• Moderate-Power WorkLoad "Kick-Probing" (EM excitation)
• Resonator Burst-Sampling & PLL "lock" acquisition (from those echoes, AFTER excitation pulses)
• Scenario #1)  Stand-By at low-power level (via pulse "blanking");  Scenario #2) Inject IH Energy at High-Power level (e.g. if PLL "locked").
• Adjust Power & support bidirectional user interface using Tap-Commands (by microphonics) and simple audible feedback, thanks to additional pulse blanking modulation.

 

But i get a feeling many wars must be won before i can even dream of buying it in eazy-go ready form.  My hope is that others shall deal with finding pre-assembled "Eval Boards" with fine-tuned Gate-Drivers and why not opto-couplers already soldered beside their associated power devices, etc.  Featured with isolated ("flux") couplers if it helps to cut delays, plus Faraday shielding to serve as a galvanic barrier if possible...

 

Whichever technology has less capacitive charges to move around this aspect should also be part of the final design trade-offs and it seems even Silicon Carbide has more capacitive parasitics potentially leading to stability issues as the "Miller" effect.  In addition, it ain't too difficult to understand that the inefficient energy transformation of electricity into internal component heat defeats the purpose of portability to some degree.  It appears desirable to me to engage into some bold experimentation trying to directly combine battery energy magnetically from each cell (sort of a "parallel" equivalent) instead of mounting those as an electrical "series" circuit;  taking profit of the GaN edge(s) i figure the workcoil must be built onto the PCBoard itself with Low-Z command tracks and High-Current drive ones, carefully distributed to prevent ground-loop troubles and what not.  Then why not include a decent amount of "shielding" in the process as i'd want to fold the precious IH field INSIDE my workcoils assembly, instead of wasting half of that into surrounding space, while on batteries...

 

Once Curie alloys and similar are being used for the susceptor it should be possible to extract quadrature-coherent I/Q signatures reflecting temperature-related parameters through a "Pick-Up" coil feeding a synchronuous demodulator, with the carrier clock directly available.  The idea here ain't to depend on some ultra-fast schottky diode which is still bound to come with its physical limitations anyway, starting with reverse-recovery issues resulting from semiconductor junction capacitance (read DELAYs)...  A PLL approach as suggested above would solve such cross-connected diodes issues 1st by exciting the "tank" resonator and then by "listening" to find a natural resonant frequency to "lock" on to.  So it means the power stage must cooperate as a "slave" of the PLL control board and not pretend to implement that as well.  Which still doesn't mean there can't also happen to be over-ride jumpers, just in case.

 

The rewards for using a more structured system begins with power efficiency as this can implement TRUE ZVS Quasi-Resonant behaviour and potentially even beyond, with the Mazzilli "Plan-B" scenario as a possible fall-back (hard-wiring jumpers) remedy for when the brain goes dead, hence in principle extending the tool's useful life expectancy.  As demonstrated in musical Tesla Coils many years ago the blanking of IH pulses paved the way to a lot more than simply just output control;  it's about "scanning" for a workload signature, receiving tap-commands and acknowledging them positively with a vibration, a sound or both.  All this vision of heavens actually require may be the trivial addition of a permanent magnet to turn the workload into a dynamic bidirectional transducer as in the good old days days of Graham Bell...

 

No KISS-inspired Mazzilli cross-connected diodes can offer that, nonetheless.

 

Good day, have fun!! 

Edited August 29, 2020 by Egzoset
Proof-reading...

[Egzoset]

ADDENDUM:

 

 

 

While practically every other "stoner"/"droÿé" on planet Itnoc seems willing to celebrate the mercantile success of dirt-cheap over-simplified neo-generic Mazzilli-topology "modules" - with ZERO return for Vladimiro Mazzilli himself i'm sure (actually sort of wondering if he's even still alive anyway!), euh...

 

On 29/07/2020 at 11:05 PM, Egzoset said:

 

 

Power Curve-Fitting Control Method with Temperature Compensation and Fast-Response for All-Metal Domestic Induction Heating Systems

 

M'well, the most fundamental aspects of IH-driving remain absent from a universe where enthousiast "experimenters" proudly ignore their own primary responsabilities vs unfinished DiY material, quite in similar fashion to those involved in such commerce, all too often describing their self-serving agenda as community service guided by popular leaders posing as "engineers" (with no engineer tools...), unable to really provide *ALL* of the relevant information to unsuspecting newbies who never heard of gate waveforms nor the slimmest hint of correctly-tuned RC "snubber" additions (read technical "WORK") to match...  The simple fact is those participants are doomed to never leave the prototyping zone because of hard-wired limitations acting as an ANCHOR attached with a very thick chain precisely.  Honestly if i were in George's boots at DynaVap i might as well wish to pay these most altruist guys for buying me time, effectively delaying over-due progress by supporting some deceiving decoys for everyone else, essentially.

 

Below here's some radio amplifier layout i picked for only 1 reason, which is about the part in RED:

 

 

Anyone sufficiently trained to read schematics will instantly recognize that's a form of AC Decoupling, somehow nowhere to be seen in Mazzilli IH scenarios besides their heavy "choke" feature(s) which by the way i consider as a truly serious issue in terms of excess mass for portable missions (especially where there happens to be a pair of them!)...

 

Still failing to address this crucial matter nonetheless:

 

Efficiency standards for external power supplies (2019-Feb)

 

We're NOT talking about an application rated below 100 mW, so here goes more responsability down the drain.  Sales MUST continue i gathered...

 

 

Personally i believe what's appropriate for stepper motors would probably work wonders if only it were on the menu to begin with:

 

 

On the left side that's illustrating how half of the force field gets dispersed into infinite space, in total absence of flux concentration...

 

The right side parts explains how flux concentration can keep our precious IH energy where it count most - INSIDE.

 

So i imagined ferrite rods energized (and maintained on their PC Board assembly) by individual glued coils would perform an equivalent task, by folding the fields toward a common focal point:

 

It may be necessary to "close" all magnetic "circuits" with more ferrite bridging the gaps around the circumference but i bet that's only going to help contain parasitic emissions better, to comply with Radio Frequency regulations, which is about showing some fair respect for the neibourhood...  Definitely NOT a design criteria of Mazzilli-topology boards found at a rebate price.

 

Never mind the hard work, Egzoset with a capital "E" is expected to fix & produce it all at absolutely no cost, no strings attached, while taking such perpetual insult with a smile i suppose!

 

...

 

Good day, have fun!! 

Edited November 10, 2020 by lildaveham
Offsite links removed

[Egzoset]

Proposal to play (& WiN) easy/fun game!!

 

 

 

 

 

And now here's one well-assorted mystery question.

 

If while simply using dynamic earphones one will effectively hear acoustic vibrations from metal/ferrite making contact in presence of a permanent magnet then what else could that do for us in the announced context of this dedicated thread?

 

 

...

 

Assume some feedback signal is mainly composed of 2 separate frequency bands which happen NOT to necessarily occur at a same time.  For example, if the "tank" resonator is energized or "kicked" there's going to be an echo even after the A.C. energy supply has stopped, because that's what a resonator does:  electric charges changing sides somewhat in similar fashion to a clock/metronome pendulum...  So, if one "listens" at those echoes it must be easy to tell which reflected signal actually follows Insertion/Removal ultrasonic (25 ~ 100 KHz) input in comparison to microphonics in the voiceband (e.g. well below he IH-specific band).  Consequently any DV VC "clicks" shall correspond to a "READY" signal most easily distinguishable from IH power drive that ain't necessarily even occuring at "LISTEN" (or sampling) time.  As a matter of fact in the sort of pulse-framing scenario i got in mind it's a basic requirement to ONLY monitor for microphonic feedback signals BETWEEN the kicks, when IH power driving is SILENCED, implicetely...

 

Quite obviously the ultrasonic echoes indicating Insertion/Removal of a consumption tool, into its associated IH workcoil (...), are dependent on sufficiently-energetic kicks on the tank-resonator workcoil although this task doesn't require a full-power regime at all.   Consequently the idea of a reduced-level kicker makes even more sense as i was going to comment on additional energy savings performed by "muting" or "blanking" those kicks completely within a 85 % range of the whole blanking sequence which would also generate input in the voiceband @ 5KHz i believe.  Meanwhile at 100 KHz (max.) 1 single 5 micro-second pulse can be sent each 10 micro-seconds, which makes 1 "pulse cycle" with 50 % on/off balance...  If the initial power-procedure equally corresponding to reset/sleep lasts 10 micro-second, a kicker cycle another 10 and then the listen phase costing 10 more then this leaves 170 micro-seconds within a 200 msec frame of 20 x 10 base-cycles to control this driver's actual output level, by blanking more or less kicks or pulses or cycles proportionately to a desired target-level reduction.  Further processing by some additional means should even provide controlled audio-feedback in order to implement a user interface with NO display nor even a button, except the power switch i guess.  Expect no Hi-Fi, but i bet MiDi-like sounds should still seem a realistic objective.

 

 

All it takes is to begin experimentations with a magnet, something anyone with an old "wired" dynamic earphone (with a coil and magnet inside) can contemplate doing if also lucky enough to have some selenoïd coil nearby...

 

In this picture above i shown a 120 Volts A.C. transformer coil assembly which already had lost its laminated power core; it sure got many more turns than any IH workcoil i'll ever contemplate using but this turns out to work wonders at generating evidence of microphonics - even stronger if using the low-voltage "secondary" (in this case 12 Volts), that's it.  Briefly put all you do is connect your used/sacrificed earphone(s) to a large coil in presence of a permanent magnet aided by flux-concentrating material - ferrite bars from an AM radio (as illustrated) proved to work just fine, more than anyone needs anyway just to realize there has to be by-product signals in the power supply chokes feeding an IH workcoil and those await an opportunity to increase a whole setup's value (while possibly also diminishing total mass of such heavy/analog "RF-Choking" circuitry i think).

 

Anyway, it seems to me that due to tight high-current coupling we can expect both Insertion/Removal and Temperature-Ready (clicker) signals would safely get obtained after some choke rewinding work, with a lower weight/profile and potential for further automation as a bonus!

 

 

Lets concatenate.  A unit can be designed to mute its power-switching circuit until completion of an initialization cycle and then repeatedly alternate between kick and listen cycles until at least 3 signals come to play:  #1) Insertion/Removal was detected via ultrasonic echo modulations;  #2) the temperature-ready clicker had flagged for attention;  #3) time-out signaling controls the pulse-blanking interval, then return this unit to its stand-by or deep-sleep state until the operator switches it off completely.

 

All rendered possible by the simple addition of a magnet.

 

 

Good day, have fun!! 

Edited November 10, 2020 by lildaveham
Offsite links and pictures removed

[Egzoset]

UPDATE.

 

 

 

The more i look at it the more it captivates my attention...

 

 

The simple fact is all along there's a major paradox in pretending that's suitable for battery-operation while in fact most of the over-simplified Mazzilli topology "module" just ain't fitting - once again by design.

 

Battery voltage level will drop progressively, which implies the feedback signal equally varies although the gate requirements remain unchanged...  So far we got MOSFET technology with heavy capacitive gate parasitics, assymetrical gate-driving combined to diode reverse-recovery issues (and more parasitic woes), etc., all in absence of any failsafe protection as some counter-measure against potentially destructive parasitic-related troubles yet to be addressed by the enthousiast experimenters themselves.

 

It should be based on power devices with much lower gate capacitances, by today's standards anyway.  Like starting with GaN 3.3 Volts "logic" (gate) switches, or at least SiC schottky cross-connected Mazzilli diodes i presume.  What i do gather with reasonable certainty is that those popular boards make a very poor match for the task in mind and the worse part of it is that such relative/circumstancial success presently serves as an ANCHOR actually blocking the path to further innovation (E.G. YES, we've known IH-driving "works" for some while now!), with multiple limitations HARD-WIRED long long ago with nobody ever willing to perform over-due corrections since at least Mazzilli worked on his clever topology, back in 2008 or so i believe!...

 

 

Good day, have fun!! 

 

 

P.S.:  Ah, and considering the high-current tight-coupling between a workcoil and its associated RF choking component(s) i'm assuming there's going to be galvanically-isolated feedback waiting to get exploited productively.  But that's only an intuition of Egzoset, so please don't trust my word for it:  check for yourselves if/when tired of just cloning obsolete/suicidal prototypes...

Edited September 12, 2020 by Egzoset
Read-proofing.

[Dodgee]

So let me get this right..

 

The thingamy jigs whatcha m'call tha diggery do da's ???

 

Have I got that straight??

[buddy13]

13 hours ago, Dodgee said:

The thingamy jigs whatcha m'call tha diggery do da's ???

 

cheers dodge, was taking me ages to try and work that lot out

[Oldbear]

I think he's talking about making a vape that's instantaneous, accurate and long lasting... Been a long time since I looked at electronic schematics so it might be a toaster

 

[Egzoset]

Lets try to put it in writing.

 

About Mazzilli-topology modules...

 

Still on semi-DiY To-Do list:

 

Revise Coupling/Decoupling
Separate i/o Power Supplies
Provide Low-Z Gate-Driving
Make LOOP battery-friendly...
Investigate all Failure Modes
Evaluate CHOKEs as SENSOR
Add/Tweak "SNUBBER" circuits

 

Those modules are unfinished prototypes and people keep replicating setups built around them somehow expecting the performance of a ready-made 3rd-party commercially-available product, which is unrealistic at best.  In comparison UK folks now have just that as an alternative which sounds like a much more promising bargain considering it addressed all those selection criterias which the magnificent & omnipotent Egzoset just mentioned for the audience's own benefit.

 

So, what more does it take to rush an order to RMCybernetics asking a few more questions aout their "CRO-SM2" for starters?  One may only wonder...

 

M'well, i'll be honest and acknwledge "Evaluate CHOKEs as SENSOR" ain't on this manufacturer's menu either, but that's quite understandable as a large power resistor was chosen to close a feedback control-loop instead.  Hence it's not really missing, just a missed opportunity to explore multi-purpose component design perhaps.

 

 

 

 

[Egzoset]

Salutations,

 

Well it seems for some reason there are groups of individuals looking after IH drivers costing them less than it costs me to get a pizza delivered by one of many local pizzerias - and that's no big town...  IMHO the tip alone would be a problem i suppose.

 

 

Today i'm going to post for the benefit of future/eventual visitors, hoping at least 1 person in the usual audience shall appreciate an update.

 

It's about bending flux lines in magnetic fields, but 1st i must emphasize the value of legacies from our fathers and their father's fathers, like this fine piece of KISS Engineering which initially inspired men of ancient Greece nearly two dozen centuries ago:

 

I should have wrote the inventor's name(s) on it, and the date(s)...

 

Apparently it's a type of problem also popular among mathematicians, which is how the expression "cardan" finally started to stick on.  Take great care in noticing that both systems are independent from each other and yet they share a central pivotal point.

 

Now here's a very different type of human invention, this time it's about the tape recorder:

 

 

A slotted toroïd core with a selenoïd bobin.

 

...

 

Finally, if we consider the properties of flux-concentrators including some commercial paste formulations especially suitable for a frequency band between, say, 30 ~ 300 KHz, then we realize the force-lines can be shaped.  Indeed, magnetic fields can be "channelled" and bent to go where these shall prove most beneficial.

 

On the left that's a classic rudimentary selenoïd with half of its force-lines unable to "close" the magnetic circuit between its 2 poles, the counterpart of it is the stepper motor, where very little energy gets lost in vain, quite on the contrary:

 

 

The "hot spots" corresponding to red and yellow are displaced deep into the stepper assembly structure, away from external boundaries and hence simplifying control of nuisible radio-frequency emissions in the neighbourhood...

 

But how much is too much for a pizza?? 

 

...

 

M'well, here's one possible configuration of a 3-Phase 9-poles scenario where the poles are series-connected as 3 groups of 3 inductors.

 

Of course i'm suggesting to seek inspiration in this stepper motor model and not necessarily that an actually-refurbished stepper motor will do the job it's expected to perform in our present context.  Its frequency range will be 1st on top of the priority list to require attention, which should determine the type of flux-concentration material, etc.  At the moment though it's already allowed to suggest the power stage will look a lot like this:

 

 

That's extracted from a stepper motor article.  RC Snubbers are clearly visible, their values obviously need revision but their purpose is evident.

 

So, to wrap it up my conclusion goes like this.  Although i'd be most curious to get 3-Phase designs fairly evaluated i think battery-operating portability restrictions would cause me to suggest a 2-Phase 4 Poles alternative instead, with 1 power cell per Phase ultimately - but that's another story.  My point is that 4 MOSFET power transistors should suffice unless one prefers advanced semiconductor integration applied to another type of device:

 

 

 

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)

 

 

 

TPA3116D2

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

 

Essentially-speaking it's been made fool-proof, designed by Ti's silicon engineers with special consideration for end customers:  the auto-radio market.

 

As a matter of fact there's no need to buy the dedicated Ti "eval"/"demo" board while its commercially-available from 3rd-party sources as a finished product, this time a really finished one i mean, which differs radically from a board initially built for Tesla Coil enthousiasts...

 

Anyway the good news here is that it's reasonably affordable and even found with BlueTooth (read "Galvanic Isolation"!!) on the later auto-radio devices.  One other great aspect of it is that Gate Driving takes place inside the chip because it's actually got 2 Full, MOSFET, integrated H-Bridges with a peak current capacity of 7.5 Amperes if memory serves me well, while its maximum power-switching frequency ranges from 400 KHz to 1.2 MHz!...  And that's just the begining of it but i'd be wasting resources trying to valorize what's shown here any further.

 

As with my challenge to DUPLICATE & PEER REVIEW Egzoset's LAVA concept the only way to find out in such fine case is to put it to trial (e.g. via 1st-person experimentation...), or continue to promote Lemons for the Lemmings!

 

 

So...  How does this relate to ancient Greece and whatnot??

 

Simple enough.  Our father's fathers have shown the solution to a 2-Phase 4-Poles IH-driver setup long before we even had electricity discovered:  the cardan layout.  Except i recommend to align it with its rotational axis to get compressed down to an overall thickness of ~10 mm (with 2 superposed 5/8" dia. IH apertures in its center...), which should be most compatible with the cigarette pack dimensions.  This will support 4 coils made of AWG copper wire #12, each with at least 3½ turns and hence 7 turns per phase, with each phase wrapped around its own magnetic circuit defined by independant flux-cencentrating material.  Obviously the bobins would be flat and only accomodate a ~3 mm thick magnetic core but i'm betting that's the way to go if we're to acquire public acceptability.  Otherwise i can foresee in my foggy story-teller crystal ball some of UK's yellow-journalism editorialists titling their articles accordingly, while there's no good reason to waste precious energy in the 1st place...

 

Please take note Ti's TPA3116D2 chip also offers direct access to its local oscillator for external synchronisation purposes while the Magnificent & Ominipotent Egzoset finds reasonable to assume that capacitive-coupling at the audio input(s) can be skipped to perform a sort of IH pulse "framing" intended to support output level control and more.  Paving the way to a generous amount of semi-DiY experimentation for the true enthousiast pioneers, not just dirt-cheap pizza eaters.

 

Good day, have fun!! 

 

Edited November 10, 2020 by lildaveham
Offsite links and pics