PopularFX
Home Help Search Login Register
Welcome,Guest. Please login or register.
2021-10-22, 10:45:10
News: Forum TIP:
The SHOUT BOX deletes messages after 3 hours. It is NOT meant to have lengthy conversations in. Use the Chat feature instead.

Pages: 1 ... 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 [29] 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 ... 81
Author Topic: Dally, Shark & Ruslan workbench  (Read 53573 times)

Group: Professor
Hero Member
*****

Posts: 2382
...but there are some differences, like that its stable with every time base step i take.
Also at the base signal frequency we "see" already some jittering from the modulation.
Indeed, this is not convincing.

However, note that triggering the scope from the perfect AM signal generated by the FG is very different from triggering it from the signal generated by the Stalker's contraption, because the latter has spikes which can trigger the scope reliably, while the FG's clean signal does not have such distinct spikes.

So I must ask whether that jitter still remains visible, when you view the AM signal from the FG while the scope is being triggered from the FG's sync output on a separate channel?

P.S.
Watch out for the "SyncMode" setting under the "Utility" button, which affects what signal appears at the Sync BNC output jack on the front panel or on the rear panel, during modulated mode or harmonic mode.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194

Well, the jittering stops, but the signal (24.4KHz base signal) slowly moves to the left.

I use the FG CH1 as output (3.8Hz modulated 24.4KHz base signal) and its (CH1) sync output (front) to trigger on.
The "SyncMode" setting under the "Utility" button" is greyed out in normal.

Itsu
   

Group: Professor
Hero Member
*****

Posts: 2382
The "SyncMode" setting under the "Utility" button" is greyed out in normal.
It should be active in the modulation mode.
The Sync outputs also have other settings in the "Utility" menu, which enable them.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194
I put a 0.1uF ceramic cap between TL494 pins 6 and 7, but no noticeable difference seen to the moving modulated signals, still drifting.

I then added 600nF to the Inductor series caps, now having 630nF and it resonates around 21KHz, but there is now some strong interaction between the  Inductor and Grenade signals as if they are figthing each other.

Need to fine tune to 24.4Khz which i will do tomorrow.

Regards itsu
« Last Edit: 2021-05-29, 09:42:01 by Itsu »
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194
It should be active in the modulation mode.

No, the opposite,  active in Sine only, when adding MOD it greyes out.

Itsu
   

Group: Moderator
Full Member
*****

Posts: 151
Enjoy your trek through life but leave no tracks
   Yet, it's the same thing that I've experienced with my very similar Stalker circuit. The push pull fets gets hot, burning hot, the grenade gets hot, my output cap(s) on the grenade output get hot, and my simple Kacher gets hot. And fans don't do enough. So, there is something wrong there.
   It does help to adjust the duty cycle, and frequency. But, the better the resonance, the higher the heat produced. So, it's a great heater, at least.
   Below is my circuit. Plus, due to the heat issues, I had to make another additional snubber circuit board to deal with the heat on the fets. But it doesn't really help that much. And I don't like to have to hear a bunch of fans going all the time.
   BTW: I don't use the big choke on the output, like is shown in your diagram. As I think that later schematic don't show it on there. Maybe it's not needed? But, I can make one, if really needed.  And no, both fets are not on at the same time. I know about that...
   Itsu, wait until you put a few hundred watts worth of bulbs on that output, plus the feed back circuit, on top of that. Toasty... 

   NickZ
in this photo you show, notice the two diodes going down to the 0 v zero line, have you tried putting a resister to damp the fly back voltage
current your generating with your inductive winding, think about it it has to go some where, so why not try dumping it back into the +v line with a bleed off
roister ?
   

Group: Professor
Hero Member
*****

Posts: 2382
...so why not try dumping it back into the +v line...
I already suggested something like this to him in this message but he prefers not to deviate from the original design any further.
   

Sr. Member
****

Posts: 253
Its (was) 3.8Hz, now its around 30Hz but moving around (just started it up).

Connecting the ground to the circuit seems to have no influence on this modulation.

Itsu


   Itsu: When that happens, it says to me that the sync is not right. As the ground line only helps, when things are in resonance.
   

Sr. Member
****

Posts: 253
I already suggested something like this to him in this message but he prefers not to deviate from the original design any further.


   I think that itsu took a swing or two at that lossless clamp design, some years ago.  Correct, I would like to stay on the Stalker type replications.
   Until death do us part...
   
   NickZ
   
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194

The "lossless clamp" design from verpies is far more superiour to all the snubber designs i have seen, but....... as i understand the text and video's from Stalker, the created BEMF and/or HF created by the push pull circuit is a key component to create the static electricity needed for the device to work.

So for the time being i think its best to follow the directions given and try to mimic the signals shown as best as possible to replicate the result.
 
If that goal is reached, then improvements (like a lossless clamp design etc.) can be implemented to further enhance the circuit.

Itsu 
   

Sr. Member
****

Posts: 253
   Itsu:
   Yes, I agree. And those BEMF pulses, that some guys would like to see quenched, may be just what is needed for us to be able to observe the desired self running effects. So,  I can deal with the heat issue, for now.  But, like I've said, there are times when there is no heat issue at all. And it may be this heating up of the components at certain frequencies, and the "fighting" that is going on, that is making your signal drift, as well.
My signals are the same between the inductor, and the grenade. About 19KHz, or so. But, even breathing on this thing can make it drift.
So, itsu why not try some ferrite in the core, to "fine tune" with.
 
  We've never seen anyone using these contraptions to light up there homes.  Is it because they like paying the electric bill? Or is it the overheating?
Yet we can see Ruslan in the field watching the sunset, while running 4000 watts worth of bulbs, for quite a while.
 If he is faking it, he is going to get tired of that. And yes, he may have purposely been set up, when he sold the one unit for $5.000, which didn't work later, as had been shown.
Hoppy's invisible wire trick...   
   BTW:  Where is that guy??? Our house detective... The expert at running his device off of a single Fet.

   NickZ

   EDIT:  This is stalkers scope shot below, showing his sync frequencies, and his relatively clean no gittering type of signals, which no one has been able to replicate.
   

Hero Member
*****

Posts: 742
   EDIT:  This is stalkers scope shot below, showing his sync frequencies, and his relatively clean no gittering type of signals, which no one has been able to replicate.

correction: this is Alexeev's scope shot.


---------------------------
The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
   

Group: Professor
Hero Member
*****

Posts: 2382
I think that itsu took a swing or two at that lossless clamp design, some years ago.  Correct, I would like to stay on the Stalker type replications.
Yes, he even made a video about it and the push-pull circuit performed nicely.
It was incorporated in the Dally's device - not Stalker's.
   

Group: Professor
Hero Member
*****

Posts: 2382
... as i understand the text and video's from Stalker, the created BEMF and/or HF created by the push pull circuit is a key component to create the static electricity needed for the device to work.
This is also how I interpret Stalker's words.

However, stating that HV flyback spikes at yoke's primary windings are necessary for the magic to occur is tantamount to admitting that the magic happens at the yoke.

The reason for this is that suppressing HV spikes at the yoke's primary windings does not have to suppress HV spikes at the secondary windings*, and this is where the remainder of the (mostly inductive) device is connected.

Transformers don't transfer HV "static electricity" like capacitors - they transfer current pulses.
Because of that, the effects of HV spikes at the yoke's primary windings are confined to the yoke.

* this routinely happens in a flyback transformer.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194

OK, agreed, but there is also mentioned somewhere that the inductor / grenade act like the plates of a capacitor in which case then the HV "static electricity" is transferred.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194

I have tuned the both coils (inductor and grenade) independently to series resonate on 24.4Khz, but when connecting them up together, none of them will resonate on 24.4Khz, instead i can tune either of them into resonance (which is lower then 24.4Khz) which seems to push the other coil out of resonance.

I have seen that before when overcoupling a bandpass filter:
https://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/qst/1991/12/page29/index.html

Not sure what the goal is here.

Itsu
   

Group: Professor
Hero Member
*****

Posts: 2382
I have seen that before when overcoupling a bandpass filter:
https://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/qst/1991/12/page29/index.html
I think this is relevant, too.
Do your tuned circuits act as overcoupled or undercoupled ones?
   

Hero Member
*****

Posts: 742
Itsu,

I have tuned the both coils (inductor and grenade) independently to series resonate on 24.4Khz, but when connecting them up together, none of them will resonate on 24.4Khz, instead i can tune either of them into resonance (which is lower then 24.4Khz) which seems to push the other coil out of resonance.
I have seen that before when overcoupling a bandpass filter:
https://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/qst/1991/12/page29/index.html
Not sure what the goal is here.

Do you think it will be possible tune inductor resonance first and then gradient coil to have current approx. 30 degrees ahead of inductor current ?

Vasik



---------------------------
The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194
I think this is relevant, too.
Do your tuned circuits act as overcoupled or undercoupled ones?

I think as overcoupled, like 2 like magnet poles pushing each other off frequency.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194
Itsu,

Do you think it will be possible tune inductor resonance first and then gradient coil to have current approx. 30 degrees ahead of inductor current ?

Vasik

I can try.

In the PDF,  what is meant in the below quote by "LC"?

Yellow trace: gradient coil current 23 degrees ahead of LC
Red: push pull LC current (through capacitor)


Itsu

   

Hero Member
*****

Posts: 742
I can try.

In the PDF,  what is meant in the below quote by "LC"?

Yellow trace: gradient coil current 23 degrees ahead of LC
Red: push pull LC current (through capacitor)


Itsu

It means inductor circuit.




---------------------------
The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194
so in that PDF screenshot, we see:

the Grenade current (yellow) 23° ahead of the inductor current (red).
   

Hero Member
*****

Posts: 742
so in that PDF screenshot, we see:

the Grenade current (yellow) 23° ahead of the inductor current (red).

Yes.


---------------------------
The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3194
Ok,  trying to get the same signals.

Using the current transformer (purple) and the AC current probe (blue) as both present similar signals (phase).

Just below resonance frequency i get the below signal see screenshot.

But changing the frequency up or down shows that when the inductor is in resonance, the grenade is not and visa versa.

Video here:  https://youtu.be/BiGxW1a2KC8

Itsu
   

Group: Professor
Hero Member
*****

Posts: 2382
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.
   
Pages: 1 ... 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 [29] 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 ... 81
« previous next »


 

Home Help Search Login Register
Theme © PopularFX | Based on PFX Ideas! | Scripts from iScript4u 2021-10-22, 10:45:10