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Author Topic: Has anyone seen Lasersabers new motor runs on 1000uf cap  (Read 294595 times)

hoptoad

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #150 on: June 09, 2013, 05:47:09 AM »
snip....
 I have a an idea that there is more efficiency in numbers of coils and magnets as compared to 1 driver coil on a rotor.
snip....

Let's assume you have one (air core) coil with a DC resistance of 8 ohms.

Instead of putting 2 times 8 ohms in series, which will obviously half the maximum current consumed for the same supply voltage, due to the doubling of resistance to 16 ohms, try putting 2 times 4 ohms in series.

In this way the total dc resistance of the drive circuit is the same, and theoretically, so is the inductance.

With 2 less variables changed, in the context of trying to compare whether 2 (or more) drive coils are inherently better than one, such a test is more akin to "comparing apples with apples", so to speak.

Cheers

Pirate88179

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #151 on: June 09, 2013, 06:27:49 AM »
Hey Bill
Well, nobody is saying OU yet. Considering the total ohms of the coils, one can calculate the current flow through the coils if they were only depicted by resistance alone. Then we have most likely huge air core inductances in series. Im gunna have to build it. This needs to be looked at with a scope for sure. Were looking at things in the very very low micro amps here. No need to assume any extra energy, just very little use of it. As I said in an earlier post, I have a an idea that there is more efficiency in numbers of coils and magnets as compared to 1 driver coil on a rotor. If it is correct, then what would happen with 24 coils, 48 coils?  And just all in series as shown. 48 coils would be 80kohm. But from what Im seeing, 48coils would do better. Then 96 coils, more mags also as we increase the number of coils. It doesnt even have to be a larger rotor, just stacks possibly.

Lol how much less can the current use get if 24 coils were used? Or 48? And still have motor action? It will be nano scale. That rotor output needs to be measured somehow. If at 24 or 48 coils it can still work against the drag of the straw, this will need some serious looking at. ;)

Mags

Mags:

OK, I did not mean OU at all.  Poor choice of words on my part...instead of "extra energy"  I should have said "additional energy".  I simply meant that possibly radio waves were adding to the efficiency of the rotor is all.  As I said, it would not take much to aid in keeping that cap a little juiced.

Anyway, it was just a thought.  Most likely it has nothing to do with it.  All those coils with that fine wire just reminded me of a crystal radio antenna is all.

We will see.  Good luck with your replication.  I wish I could make a nice 3D printer.  Those things are the machines of the future I believe.

Bill

Magluvin

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #152 on: June 09, 2013, 06:40:05 AM »
Let's assume you have one (air core) coil with a DC resistance of 8 ohms.

Instead of putting 2 times 8 ohms in series, which will obviously half the maximum current consumed for the same supply voltage, due to the doubling of resistance to 16 ohms, try putting 2 times 4 ohms in series.

In this way the total dc resistance of the drive circuit is the same, and theoretically, so is the inductance.

With 2 less variables changed, in the context of trying to compare whether 2 (or more) drive coils are inherently better than one, such a test is more akin to "comparing apples with apples", so to speak.

Cheers

Your right. no need to just have high ohms to experience the gain. The Bose 901 speakers were 9 small speakers 1ohm each in series. If I remember they were 4in drivers. But it sounded like a lot more than what you see. ;)

The comparison would be simpler to just check the rotor rpms with one coil compared to 2 coils in series with the same input.  Im setting up the experiment right now using 2 coils. Will see what happens. ;)   They are not 1.7kohm coils. lol But like I said, it should work either way..  My electric bike hub motor uses 52 coils and 52 neos bout 1/8x1/2x1 and puts out near 1 hp. I cannot even think of that much mechanical power coming from a single coil motor.  ;) The huge coils and large magnets to do so would not be convenient nor sightly. :o ;) My bike motor is not an exact configuration but just an example. It has side by side magnets and EZ doesnt. Would like to see EZ with 12 mags filling in the spaces between the existing ones. If it is a reed switch timing issue a small bias magnet can be used on the outer end of the reed so that it only fires on the N mags. Works very well and can help fine tune the timing. Reeds are strange buggers. Here is a vid I did long time ago where using just a small drill bit I could reverse my rotor, which was a diametric neo mag. Start at 1:00 to 1:20 and then to 2:30 into the vid to get right to it. ;) Or you can watch the whole thing. Its old.
http://www.youtube.com/watch?v=qYgs7dvyZqc


One really must think about what running that motor on 1ua really means. Look at it. Watch it. See what he does with it. An LED is typically 20ma. This is 1ua. And just imagine taking it steps further. ;)

Mags

Magluvin

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #153 on: June 09, 2013, 07:00:28 AM »
Mags:

OK, I did not mean OU at all.  Poor choice of words on my part...instead of "extra energy"  I should have said "additional energy".  I simply meant that possibly radio waves were adding to the efficiency of the rotor is all.  As I said, it would not take much to aid in keeping that cap a little juiced.

Anyway, it was just a thought.  Most likely it has nothing to do with it.  All those coils with that fine wire just reminded me of a crystal radio antenna is all.

We will see.  Good luck with your replication.  I wish I could make a nice 3D printer.  Those things are the machines of the future I believe.

Bill

Hey Bill

I think its a matter of more coils. Even though in series as the energy use decreases compared to 1 coil, the spread of all those little energies over the span of the rotors edge can account for more rotor motion than if that same total input energy was just focused on 1 coil alone acting on 1 magnet alone.  Makes sense and we will find out if thats the case shortly. Im doing a comparison of 2 series coils vs 1 coil. From my speaker analogy, the 2 in series should make the rotor go faster than the 1 coil while the 2 use half the input of the 1. And if thats the case, then 4 coils using 1/4 the input of one should produce even more speed that 1 or 2 coils. Will be weird if it is so. How far can we go with that. :o

Mags
 

Magluvin

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #154 on: June 09, 2013, 07:12:39 AM »

 An LED is typically 20ma. This is 1ua. And just imagine taking it steps further. ;)

Mags

I did some tests a while back. I used 'glow powder' which can be used in paint to see if it would power a solar cell after being lit from UV leds. The glow powder if hit with light for 2 min will stay lit over a period of 8 to 15 hours. From my tests, this would power that motor with more than 1ua at the voltages it can run at. Ill have to see if I still have that stuff.  My goal was to light the powder on the surface of the cell and then let the cell charge a super cap or battery enough to run the 2 min light cycle again. I wasnt into the JT at the time and that may have made a difference. Will have to see if the glow powders have been improved since.

Mags

Pirate88179

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #155 on: June 09, 2013, 08:18:20 AM »
Mags:

Have you seen this stuff?

http://www.batterystation.com/curtisium.htm

Cutisium.  I bought some of these tiles a few years ago and, to me, it is the state of the art in glow technology.  Stick a few tiles in the sun for a minute, and they glow very brightly for 12-20 hours.  Incredible!  I can charge them with the light from a cfl, or LED light and they glow so brightly and for such a long time, it is amazing.  One day, I will build a house that has a wall of these that gets sun exposure during the day, and lights the room at night.

Bill

conradelektro

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #156 on: June 09, 2013, 12:03:38 PM »
conradelektro,

I believe the reason why (your motor requires more power) is the amount of energy needed to overcome the inertia. Your rotor with the magnets is larger in diameter, weighs more, etc. It's a matter of greater mass and weight, I would think would be the reason why your motor requires greater energy to turn vs LaserSaber's motor.

What if you were to make your rotor out of Balsa Wood structure capturing the magnets, held in place with super glue? And the diameter was the same as LaserSaber's? (Note: Cut out as much material from the rotor as possible without weakening it to make the rotor as light as possible)

To run an equivalent energy efficient device you'll need to match or improve on it's ability, no?


@Billxx: I like if someone speaks up, only the exchange of opinions allows us to learn. I was thinking along this line as well (inertia, mechanical problems, wrong dimensions,..) but now I believe:

If a magnet of the rotor is near the Reed switch current flows. And this current is mainly determined by the DC resistance of the coils as long as we have very low frequency (like one rotor turn per second). So, measuring this current (when a magnet is in front the Reed switch) gives us an upper limit of the power draw of the motor.

For my motor this upper limit at 1 V supply Voltage is 1/540 = 1.8 mA (6 coils in series with 90 Ohm DC resistance each).

When the motor turns the Reed switch ON-time is about 20%, so, 1.8/5 = 360 µA. In fact I am measuring about 500 µA because the ON-time is may be a bit more than 20%, more towards 25% (results in 450 µA average power draw).

My motor turns with about 150 rpm with 1 V and 500µA, so all mechanical and wrong dimension problems are overcome with this power draw. By introducing a resistor into the circuit, e.g. a 5.6 K resistor I could bring the average power draw down to about 50 µA, but then the motor hardly turns (about 30 rpm and every disturbance stops it). So, the mechanical problems can be overcome with 1 V and 50 µA.

The reverse current of 10 1N60 germanium diodes (about 20 µA at 1 Volt) were not enough to make my motor turn. So, I would say that my motor needs at least 1 Volt and 50µA to turn, but I can not bring its power demand below 1 V 500µ A without introduction of further resistance into the circuit.


Sorry for the delay.  The coils seem to very between 1.6 to 1.7K.  The resistance on the six coiler is 9.9K.

No lets do the upper limit calculation for Lasersaber's motor with 6 coils in series 9.9 K DC resistance at 1 Volt supply Voltage:

1/9900 = about 100 µA

with about 20% Reed switch ON-time we get about 20 µA average current.

My motor runs nicely with 500 µA and very slowly with 40 µA, so, therefore it is plausible that Lasersaber's very well and precisely  built motor runs fast with 20µA and rather slowly with 1 µA average power draw.

I would say the explanation of the low power draw of Lasersaber's motor lies in the 9.9 K DC resistance of his coils, and then once we have this low power draw the mechanical advantages come into play as well.

What I want to say:

First one needs that very high DC resistance (impedance) of the coils and then a good mechanical build.

Let's say I get such 1. 6K to 1.7 K DC resistance coils and put them into my motor. It could happen that it will not turn (because of the bad build), but its power draw (after pushing it along by blowing a bit of air over it) will be as low as in Lasersaber's motor.

And I will build a motor with 1.6 K DC resistance coils from relays which I already found:

http://www.conrad.at/ce/de/product/503091/Serie-36-DC-Printrelais-Finder-361190244001-24-VDC-1-Wechsler-10-A-30-VDC250-VAC-AC1-2500-VA (R-Spule = 1600 Ohm, R-Spule = DC resistance)

http://www.conrad.at/ce/de/product/503614/Miniatur-Print-Relais-AZ943-15-A-Zettler-Electronics-AZ943-1CH-24DE-24-VDC-1-Wechsler-Max-15-A-Max-30-VDC300-VAC

It may be will not turn (because of mechanical problems) but it will have a similar low power draw.

But of course I hope it will turn at least slowly.

Greetings, Conrad

gyulasun

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #157 on: June 09, 2013, 12:24:14 PM »
Hi Conrad,

Thanks again for doing the tests across the reed with the scope on it I still digesting your conclusions from it, pondering on how the diode reverse resistance plays its role.

On your latest post:  I assume those 1.6 kOhm relays from Conrad include a ferromagnetic core, can you remove them easily or no problem with them. 

Yes, the some uA current draw can only be explained by the huge impedance of Lasersaber coils (besides the big DC resistance the residual inductance must be in the some 10 times Henry range) and the small mass of the rotor.

Thanks, Gyula

conradelektro

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #158 on: June 09, 2013, 12:36:00 PM »
I did some scope shots over the diode in order to show what happens while charging the cap. No battery in the system, the cap was first discharged and the charge up to the given Voltage by blowing an air jet over the rotor rim area.

One sees that the charging happens when the Reed switch is on (positive bump is cut of because the current runs into the cap) and the again with the BEMF spike. The positive bump of the AC current generated in the coils is cut off at the momentary cap Voltage.

Greetings, Conrad

conradelektro

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #159 on: June 09, 2013, 12:49:50 PM »
Hi Conrad,

Thanks again for doing the tests across the reed with the scope on it I still digesting your conclusions from it, pondering on how the diode reverse resistance plays its role.

On your latest post:  I assume those 1.6 kOhm relays from Conrad include a ferromagnetic core, can you remove them easily or no problem with them. 

Yes, the some uA current draw can only be explained by the huge impedance of Lasersaber coils (besides the big DC resistance the residual inductance must be in the some 10 times Henry range) and the small mass of the rotor.

Thanks, Gyula

@Gyula: I hope that the scope shots over the diode will enlighten you. Feel free to indicate further scope measurements, I want to understand this motor fully. But I am not very skilled at electronics, so any help and any ideas are appreciated.

I have to first order the relays. Then I can dismantle them and look at their design. I hope that I can remove everything from the coils including the core. It was possible with the two types of relays I use so far (I called them "black coils" 280 Ohm and "white coils" 90 Ohm DC resistance). I still have the cores from the "black and white coils" and could reinsert them if needed. The motor in my old YouTube video (http://www.youtube.com/watch?v=MEEjlYvZ5OM) has the "black coils" with the cores still in place. Also my "ring magnet spinner" features the "black coils" with cores, see e.g. http://www.overunity.com/11350/confirming-the-delayed-lenz-effect/msg359314/#msg359314

I will order the two relay types indicated, 10 each, the loss will not be overly high in case of problems. I can break four and still have six.

Greetings, Conrad

wattsup

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #160 on: June 09, 2013, 04:31:38 PM »
@conradelektro

I would like to remind you and everyone else that if you use a diode, don't expect to find the best one on your first try. This applies to germanium diodes as well when they are specifically required.

http://www.youtube.com/watch?v=nj0ShZV6bhY

I know I seem to repeat myself but you really are not aware of how much difference one diode will make compared to another of the same range or rating. This applies to solid state or motor driven, does not matter. You still need to hunt for the right diode. They are like women, each one as finicky as the next and only one will really do for a given job. Or better said, you need a Harem of diodes to run a good work bench. hahaha

Try and find as many diode models as you can. If you only have one or two it is not enough to hunt for the right diode.

The other point is this. Using the reed at the negative side of the coils is OK, but again, experimenting means trying all options, like on the positive side or even between coils 3-4 or other mix. The point is that when you pulse on the negative, the positive will already be in the coils and the change inside the coil may be minimal. If you pulse on the positive side, the negative will already be in the coils and now the positive has to "move" (hate that word) into the coils thus creating more change and possibly charging your cap to a higher energy state.

It is good now that you are testing without a feed source.

The other point is @lasersabers coils alternate NS. Are yours? If not maybe switch the wire directions on each second coil.

Ideally, given that your 6 coils are spread apart rather generously, you may consider adding more magnets to your rotor. 12 magnets would be very generous but maybe just add 1 or 2 more magnets creating an off timing effect that your spread coils may enjoy more then a sparsely timed impulse.

@lasersaber

Can you measure the inductance of one of your coils.

Also, I am leaving you a post on your web site.
http://laserhacker.com/forum/index.php?topic=155.msg1662#msg1662

wattsup

Added: A great web site for reeds......
Nice 3-way reeds here........
http://www.meder.com/spdt-switches6.html
Check their Section entitled Reed Switch Resources.

conradelektro

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #161 on: June 09, 2013, 05:46:53 PM »

A) I would like to remind you and everyone else that if you use a diode, don't expect to find the best one on your first try. This applies to germanium diodes as well when they are specifically required.

B) The other point is this. Using the reed at the negative side of the coils is OK, but again, experimenting means trying all options, like on the positive side or even between coils 3-4 or other mix. The point is that when you pulse on the negative, the positive will already be in the coils and the change inside the coil may be minimal. If you pulse on the positive side, the negative will already be in the coils and now the positive has to "move" (hate that word) into the coils thus creating more change and possibly charging your cap to a higher energy state.

It is good now that you are testing without a feed source.

C) The other point is @lasersabers coils alternate NS. Are yours? If not maybe switch the wire directions on each second coil.

D) Ideally, given that your 6 coils are spread apart rather generously, you may consider adding more magnets to your rotor. 12 magnets would be very generous but maybe just add 1 or 2 more magnets creating an off timing effect that your spread coils may enjoy more then a sparsely timed impulse.

wattsup

E) Added: A great web site for reeds......
Nice 3-way reeds here........
http://www.meder.com/spdt-switches6.html
Check their Section entitled Reed Switch Resources.

Ad A) I saw that with my ten 1N60 germanium diodes and will check my other diodes. Important hint, thank you. Diodes for higher Amperage should have a higher reverse current. With the high impedance coils (generating a higher AC Voltage at rather low rotor turn rates) a forward Voltage of 1 Volt should not matter. To reach a 100 Volt charge in the cap like Lasersaber requires may be 1000 to 2000 rotor rpm, but 20 Volt should be possible with a few hundred rotor rpm.

Ad B) I also tried the circuit as Lasersaber describes it (pulsing positive side of the coil chain) but could not see any beneficial effect. But the effect might be smaller than my measuring precision.

Ad C) As I understand Lasersaber's videos, his 6 coil Version has all six coils in the same direction (like my replication). But his 12 coil version has them in alternating directions, and on his new 12 coil version (conical coils) he can easily change coils in order to try many combination.

Ad D) In my next version I want to have at least two different rotors and coils that can be replaced easily to try out many possibilities (different number of magnets on different rotors and different coils). If you have not yet started to build your version take that into consideration.

Ad E) I have Reed switches from Meder. Look at Lasersaber's video for optimal placement of the Reed switch, I can confirm his placement. My original placement (vertically) was also o.k. but less reliable. My early concern with Reed switch ON-time does not seem to be very important after all.

I just saw that the black relays I have chosen also come in 3600 Ohm DC resistance and even 6400 Ohm DC resistance versions (see the attached PDF files). The white relays come also in a 6400 Ohm DC resistance version (look farther down in the documents, there is a table for different versions). But the 1600 Ohm DC resistance versions should be the best ones (taking Lasersaber's build experience into consideration).

So, if you are looking for relays to take coils from them, look for 24 V relays (nominal Voltage of coil should be 24 VDC), the coil should then have a DC resistance of around 1600 Ohm.

May be one can build a 12 coil motor with 6 coils having 3600 Ohm as drive coils and 6 coils having 1600 Ohm as generator coils. But that would be much too simplistic.

Remark:

I do not want to criticise Lasersaber's way of presenting his builds, but the crucial information is the DC resistance of his coils and much mystery would have been clarified if he had given this information (which is very easy to measure) in his first video. My replication was at a loss from the beginning (with the 90 Ohm DC resistance coils). But building it helps me and others to build a new better version. So, well, everybody should do what he thinks is best. I could have waited a bit with my replication.

Lasersaber's 3D-printed motors are a very nice idea and a great implementation, so I am grateful that he shows details at all. Just with the cap, speeding up the rotor by blowing an air jet over it till the cap charges to 10 Volt or even 100V and then having it run many minutes on this charge is a nice touch. A true novelty item. I am not very optimistic that this leads to OU. But I rather try to achieve OU with µA instaed of with 1000 A. At least one can fool oneself and others more easily with µA.

Greetings, Conrad

conradelektro

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #162 on: June 09, 2013, 06:24:25 PM »
If it is a reed switch timing issue a small bias magnet can be used on the outer end of the reed so that it only fires on the N mags. Works very well and can help fine tune the timing. Reeds are strange buggers. Here is a vid I did long time ago where using just a small drill bit I could reverse my rotor, which was a diametric neo mag. Start at 1:00 to 1:20 and then to 2:30 into the vid to get right to it. ;) Or you can watch the whole thing. Its old.
http://www.youtube.com/watch?v=qYgs7dvyZqc

One really must think about what running that motor on 1ua really means. Look at it. Watch it. See what he does with it. An LED is typically 20ma. This is 1ua. And just imagine taking it steps further. ;)

Mags

@Mags: I just looked at your video that also shows the drill bit as a Reed switch shield. Great stuff, goes into my collection of good ideas in connection with Reed switches. I am also amazed about how far your Reed switch is away from the turning magnet in this video.

Greetings, Conrad

conradelektro

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #163 on: June 09, 2013, 06:31:31 PM »

Might it be possible that all of that very fine wire is acting as an antenna of some sort?  Possibly capturing a little bit of all of that broadcast energy floating around out there?  It would not take much to help to charge that small cap.

I am not saying laser is doing anything untoward here, just positing a possible explanation of where some "extra" energy might be coming from.  Just a little might go a long way with his well designed rotor.

Bill

I could get some µA when placing a 10 meter long antenna near an electric 220V appliance which was on (refrigerator, heating element, coffee machine). It looks like one can drive Lasersaber's motors with that (after rectifying the small AC current). But one also needs an earth connection.

A Joule thief with a bigger air coil placed under the table could also run Lasersaber's motors via an induction loop (and rectifier). But we do not want to cheat, don't we?

Greetings, Conrad

gyulasun

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Re: Has anyone seen Lasersabers new motor runs on 1000uf cap
« Reply #164 on: June 09, 2013, 10:39:31 PM »
Hi Conrad,

Basically I agree with your conclusions in your Reply #144 and Reply#162 on the operation of this setup. Regarding Lasersaber's remark in his Reply #136 (no need for a diode under 5V) I wonder if there is any need for a diode above 5V either because I think the role of the diode is played by the reed switch (a controlled switch can act as a rectifier). I say this because when the reed is ON, the induced voltage in the coils can charge the cap whenever its polarity is correct and its instanteneous amplitude is higher than that of the capacitor. And when the reed is OFF then I cannot see what or where is the load which can discharge the capacitor, perhaps the 1 picoFarad (or less) self capacitance of the open reed switch can close the circuit at the AC frequency the rotor just runs at (definitely with MegaOhm series impedance) but not DC-wise, right?

Perhaps you could run the same test you showed in your Reply #144, third scope shot, when there was no battery but you used the diode: now in the same setup if you remove the diode or just bypass it with a wire-short and see the voltage across the reed switch, using approximately the same rotor speed.  (I guess you will find more or less a similar waveform like the one across the reed in your second picture (Scope 10 Ohm Reed.png) of your reply #139 where you used no diode but you used 1V from power supply to drive the motor.)
Apart from the diode's role, I believe the basic operation is revealed by your excellent tests, at least with respect to the schematic WE believe AS is assembled by Lasersaber, because he has not given full disclosure on his actual setup. (Not that he should give, of course, and what he shared so far is certainly commendable, albeit I agree he ought to mention coil details much earlier.)

Thanks, Gyula