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Author Topic: Dally, Shark & Ruslan workbench  (Read 218461 times)
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I tried simulating this in LTSpice.
If I get resonance on inductor with 0.7uF then to resonate both inductor and grenade I need 0.35uF
Grenade current phase depends on load and I can't get it 30 degrees ahead of inductor.
Coupling coefficient probably different from real coil, but I don't think it makes major difference.
Perhaps tuning for two frequencies wasn't bad idea after all.

So, I think we have two options now
- go back to two frequencies variant
- do not tune grenade into resonance, just put there some small cap to keep HF circuit closed

Vasik

   

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So the purple current is maximized when the blue current is minimized and 180º out of phase.
I wonder what would happen if you reversed the coupling between them.

Yes,   wondering the same, will try it.
   

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I tried simulating this in LTSpice.
If I get resonance on inductor with 0.7uF then to resonate both inductor and grenade I need 0.35uF
Grenade current phase depends on load and I can't get it 30 degrees ahead of inductor.
Coupling coefficient probably different from real coil, but I don't think it makes major difference.
Perhaps tuning for two frequencies wasn't bad idea after all.

So, I think we have two options now
- go back to two frequencies variant
- do not tune grenade into resonance, just put there some small cap to keep HF circuit closed

Vasik

Good idea to simulate.

I can try the 12.2 / 24.4KHz relation as mentioned earlier.

Itsu 
   
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I can try the 12.2 / 24.4KHz relation as mentioned earlier.

I guess it will be similar to 122Khz/24Khz mode.

Vasik
   

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I tried simulating this in LTSpice.
Please name the L1, L2, L3.
   
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Please name the L1, L2, L3.

Isn't that obvious ?
L1 - inductor
L2 - gradient coil
L3 - 3 turns coil on yoke

Vasik
   

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I miss the 18 turn coil (on yoke) in series with the grenade (gradient coil).
   
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I miss the 18 turn coil (on yoke) in series with the grenade (gradient coil).

Yes, you right.
Do you know what is it inductance ?

Vasik
   
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May be something like this ?
   

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Yes, you right.
Do you know what is it inductance ?

Vasik

Its 124uH @ 10KHz.   

L3 (5 turn coil) measures 13.5uH @ 10KHz
   

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So the purple current is maximized when the blue current is minimized and 180º out of phase.
I wonder what would happen if you reversed the coupling between them.

Yes,   wondering the same, will try it.


This changes a lot, both currents now peak around the same (22.2KHz, a little low) frequency with almost no phase shift between them:

Using the current transformer (purple for inductor) and the AC current probe (blue for grenade) again in screenshot 1.

Using the single AC/DC current probe  (measuring one after the other, white Inductor, green grenade) in screenshot 2.

Like they work together now instead of fighting each other.

Itsu
   
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Its 124uH @ 10KHz.   

L3 (5 turn coil) measures 13.5uH @ 10KHz

With proper inductance values 0.7uF and 0.35uF gives more or less stable result.
Not sure if it has any practical value.

Vasik
   

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Like they work together now instead of fighting each other.
Now, the authors should clarify which configuration was intended.
   

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Yes, that would be nice.

I now have a cross of the 5(3) turn secondary compared to the drawing below.

Itsu
   
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Here a transcript of Alexeev's video about tuning here.
May be it helps.

Vasik
   

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Thanks Vasik,

so he uses a ½ wave length inductor (19m) instead of my ¼ wave.

Also he mentions the difference in resonance frequency when the grenade and inductor work together or separate like i notice.

The 180° phase shift he mentions at 2:10 is also interesting which leads me to think that the 180° phase shift i saw earlier (before i swapped the inductor leads) is needed.

But the remark at 3:25 about the grenade winding direction (now in one direction) confuses me again.


Anyway, guess i wire it up again as i had (according to the diagram) and try to match up the resonance frequencies of grenade and inductor.


Itsu
   
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Itsu,

But the remark at 3:25 about the grenade winding direction (now in one direction) confuses me again.

I think this is old video and he reefers to some previous versions of gradient coil windings.
So you can safely ignore it.
Also about inductor length, my understanding is that both 1/4 and 1/2 will work.

Vasik
   

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Also about inductor length, my understanding is that both 1/4 and 1/2 will work.
...and that surprises me because 1/4 wavelength devices usually behave diametrically oppositely to 1/2 wavelength devices.
« Last Edit: 2021-05-31, 13:39:22 by verpies »
   

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Enjoy your trek through life but leave no tracks
Hi all Question, has any one sucsesfuly managed to create the standing wave yet ?

Regards  Sil
   
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  And it may get even more confusing, if we keep going from one guy's build to the other guy's build. 
  If Stalker's way doesn't work, (and it didn't for me), then what? Three different guys got the simple kacher working towards self running, but, I could not.
  All of these variation are copies of Akula's work, redone by Ruslan, and replicated by different people in their own way.
  So, it seams to me that the only actual relation between the inductor/grenade/ and the Kacher, Is Luck. I have not seen it line up in the way that some people believe it should. And every ones device is running at different frequencies, winding with different wire, and different cores, and caps, and...what's with the 37.5 or 40, or 41meter grenades. Is that a magic number, as well?
BTW, I do use the 1/2 wave inductor. I've also tried the 1/4 wave, as well, but it did not do as well as the 1/2 wave inductor.
And also the location, may have everything to do with it. Guys living in the US maybe not be able to use the same exact frequencies as in Russia.
  Makes me wonder if Kapanadze knew about all this stuff. And then some guys make it work without a needing the grenade, or having to use two separate circuits, but just needed one combined circuit. Again, if true, like with the Roma (Poma) device. I realize that some guys here many not know about him. Nor do I want to further confuse the issue, so I'll leave it at that.

   NickZ
« Last Edit: 2021-05-31, 20:06:41 by NickZ »
   

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Hi all Question, has any one sucsesfuly managed to create the standing wave yet ?
"Standing wave" on a scope's display ...or a standing wave somewhere else ?
   
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   Perhaps, the question is, are any of these standing waves actually essential, and make for self running? And, why at those frequencies?
As, I've never seen a video of a self runner reading @ 24KHz.

   Any ways,  itsu, seams like your scope shots are now looking very similar to mine, when you tune both circuits to the same frequency. Although, I'm just a little lower in frequency, at around 19Khz or so.
   I tune the 18.75m inductor first, by finding which 1000-2000v WIMA caps provide for the highest output voltage there. At least a single 0.47uf, then adding more on top. Then, I do the same for the grenade's output. I don't look for set frequencies. Nor have I found any that work for me. Just my own tinkering and tuning efforts. I just wish that I had a whole assortment of those German made WIMA caps to tune with, as that would really help.
   Remember that tuning should be done with the Earth ground line, attached. At least, that's what I think. Your views are on all this, are always very welcome.

   Vasik: Thanks for the tip on who's scope shot that was. Yet, it is different from all the rest, as always.
   

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Nick,

Those last screenshots where taken with a cross in the inductor leads as compared to the drawing i showed.
How are your coils hooked up, similar as that drawing or do you have a cross in it somewhere too?


I am now back to exactly that drawing, and have again the 180° phase shift on the Grenade current the moment i get into resonance on the inductor current.
The problem is that at that same moment, the grenade current dips and the bulb(s) go out.

Itsu
   

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Enjoy your trek through life but leave no tracks
  And it may get even more confusing, if we keep going from one guy's build to the other guy's build. 
  If Stalker's way doesn't work, (and it didn't for me), then what? Three different guys got the simple kacher working towards self running, but, I could not.
  All of these variation are copies of Akula's work, redone by Ruslan, and replicated by different people in their own way.
  So, it seams to me that the only actual relation between the inductor/grenade/ and the Kacher, Is Luck. I have not seen it line up in the way that some people believe it should. And every ones device is running at different frequencies, winding with different wire, and different cores, and caps, and...what's with the 37.5 or 40, or 41meter grenades. Is that a magic number, as well?
BTW, I do use the 1/2 wave inductor. I've also tried the 1/4 wave, as well, but it did not do as well as the 1/2 wave inductor.
And also the location, may have everything to do with it. Guys living in the US maybe not be able to use the same exact frequencies as in Russia.
  Makes me wonder if Kapanadze knew about all this stuff. And then some guys make it work without a needing the grenade, or having to use two separate circuits, but just needed one combined circuit. Again, if true, like with the Roma (Poma) device. I realize that some guys here many not know about him. Nor do I want to further confuse the issue, so I'll leave it at that.

   NickZ
A standing wave at 25khz
« Last Edit: 2021-06-01, 14:44:11 by AlienGrey »
   

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A standing wave at 25khz
This is not a standing wave. This is an amplitude modulated HF signal.
A standing wave has space on the horizontal axis - this wave has time.
   
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