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Author Topic: Dally, Shark & Ruslan workbench  (Read 114604 times)

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Buy me a beer
Found information about wire Sergey Stalker using in youtube comments

Well that is standard European house cable except 4mm is pretty heavy stuff, will conduct a lot of Kw

http://www.daxx-usa.com/acoustic_cables/s38-s32.htm

Is the Daxx cable on the bench.

What I have shown you is also used for speakers, very very low resistance and excellent insulation (200ºc) and I use for "capacitance" .

Regards

Mike 8)



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It's not as complicated as it may seem...
Is anyone here archiving and making available all these videos?

Being that they are on youtube, they could disappear any day.
   

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Is anyone here archiving and making available all these videos?

Being that they are on youtube, they could disappear any day.

I have downloaded many videos, and I would suggest everyone interested in this topic do the same.

PS Some more comments from that video
« Last Edit: 2021-04-17, 20:18:10 by Vasik041 »


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Found information about wire Sergey Stalker using in youtube comments
For a solid circular conductor 2*(4mm2/π)0.5 = 2.256mm diameter.

However, packing 56 circular strands (each 0.3mm in diameter) in a bigger circle requires the bigger circle to be 2.521mm in diameter ...which is +10.5% larger than the diameter of a solid circular wire with the same cross-sectional area, resulting in only 79.3% utilization of this area.
The combined  cross-sectional area of 56 x 0.3mm strands is 3.958mm2 when the air gaps between them are not counted.

https://upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Disk_pack19.svg/480px-Disk_pack19.svg.png
Dally, Shark & Ruslan workbench


So this explains how a ~2.5mm diameter stranded wire can have a ~4mm2 cross-sectional conducting area.

P.S.
The thickness and the material that the insulation is composed of, greatly affects the interturn capacitance of any coil wound with this wire.  The interturn spacing effects it, too.
   

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Agreed,   my H07V-K wire (2.5mm² core and 3.4mm outer diameter) measures 1.9mm core diameter, while 2.5mm² supposse to be 1.784mm diameter.

It consists of 40 x 0.25mm diameter strands which calculates to be 1.96mm².


So 4mm² it is.                 I have removed my earlier post,     thanks verpies

Itsu
   

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Itsu,

Could you please make a test again with slightly bigger power from SG ? (1/2 wave mode, sine)
There is small second peak, I guess it is not registered because it too low ?

I am thinking that Sergey had around 2.7Mhz single layer coil (LC and wave resonances matched), then he got 910K wave and 4.6M LC resonance after rewound.
You have around 2.4M with single layer coil, 613K wave resonance and this small peak should be LC resonance.

Does it make sense ?

Vasik

PS so the overall idea is that with gradient coil we do not match LC and wave resonance directly (1:1) but with harmonics, that is what Sergey show in "selecting push pull frequency" video (pp.pdf)


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Vasik,

you mean these below peaks 2 and 3?

Itsu
   

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Itsu,

Yes, so second frequency for tuning with your coil is 3.6Mhz
Thanks for the test!

But... it looks different now. On previous picture it was lower. Do you know is it accurate ?

Vasik


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Hmmm,  yes i see what you mean,  its around 1.5Mhz.     But its not there now somehow and the setup is still the same as yesterday.


Let me try to find out why its not there now, probably tomorrow.

Itsu
   

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Yes, I also need to rest.
Below -70db it is unlikely to be accurate.

Vasik


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I made a single loop with the SA probe (instead of open connection against the grenade) and this seems to pick up some more signals (FG max 20Vpp sine wave @ 613KHz).

Itsu
   

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I made a single loop with the SA probe (instead of open connection against the grenade) and this seems to pick up some more signals (FG max 20Vpp sine wave @ 613KHz).
If that 613kHz signal feeds a low reactance coil, then this 20Vp-p signal from the 50Ω FG would be loaded down to millivolts.  Measure the voltage amplitude across this coil to see if it is a problem.
If that is a problem, then the solution to this would be your EL2009 low impedance follower. It works down to DC ...and protects the FG's output, too.
   

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Itsu,

It could be that version 2 winding style have smaller capacitance,
because one wire goes between layers. It probably affects these higher frequencies resonances.
May be you can try it at some point.
Other option would be probably try 4mm sq wire.

Vasik


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If that 613kHz signal feeds a low reactance coil, then this 20Vp-p signal from the 50Ω FG would be loaded down to millivolts.  Measure the voltage amplitude across this coil to see if it is a problem.
If that is a problem, then the solution to this would be your EL2009 low impedance follower. It works down to DC ...and protects the FG's output, too.

Yes, Stalker mentioned (gct.pdf page 1) that not much will be left across the coil using a FG at 10Vpp and a single loop to excite it:

"there will be 0.45v on the one turn coil (because of 50ohm output)"


So i can put the EL2009's in action to pump it up.


Itsu 
   

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Itsu,

It could be that version 2 winding style have smaller capacitance,
because one wire goes between layers. It probably affects these higher frequencies resonances.
May be you can try it at some point.
Other option would be probably try 4mm sq wire.

Vasik

I think i will go for the 4mm² wire to match as close as possible the circumstances / hardware.

Meanwhile i will be building the pushpull / synchronizer (TL494 / 4093's).

Itsu
   

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I think i will go for the 4mm² wire to match as close as possible the circumstances / hardware.
In my opinion, while replicating these type of devices, the coil (or transformer) construction is very critical (including insulation material of the wire), so I applaud your decision to replicate this component as close as possible to the original.

Meanwhile i will be building the pushpull / synchronizer (TL494 / 4093's).
However, signal generating circuits are not critical at all, when the target waveform is known. In fact, most of their functionality can be replicated with your FG alone (minus the high power components). Bursts of multiple pulses (пачки импульсов) are a piece of cake for your FG at any frequency ...up to its rating.
In my opinion, the signal generating portion can even be improved by using automatic phase tracking techniques like we once did by combining the TL494 with the 74HC4046 PLL.
« Last Edit: 2021-04-20, 12:03:40 by verpies »
   

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Enjoy your trek through life but leave no tracks

In my opinion, the signal-generating portion can even be improved by using automatic phase tracking techniques like we once did by combining the TL494 with the 74HC4046 PLL.
verpies Hi; yes the later would be a good move, you say once I don't suppose you have a pointer to that idea or a box link drawing ?

Regards SIL

Itsu Question, Also re the grenade drawing notice the purple link wires well are they part of the wind and if so does it affect the wave length node position or what side of witch coil or are the extra bits in the wind length of or are they invisible to the wind and purity of the coil it self  ?
   

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Buy me a beer
verpies Hi; yes the later would be a good move, you say once I don't suppose you have a pointer to that idea or a box link drawing ?

Regards SIL

Itsu Question, Also re the grenade drawing notice the purple link wires well are they part of the wind and if so does it affect the wave length node position or what side of witch coil or are the extra bits in the wind length of or are they invisible to the wind and purity of the coil it self  ?

I am going to answer, that would depend on if you injected another signal at that node!!! it is as simple as that.

Regards

Mike 8)


---------------------------
"All truth passes through three stages. First, it is ridiculed, second it is violently opposed, and third, it is accepted as self-evident."
Arthur Schopenhauer, Philosopher, 1788-1860

As a general rule, the most successful person in life is the person that has the best information.
   

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Verpies Hi; yes the later would be a good move, you say once I don't suppose you have a pointer to that idea or a box link drawing ?
I cannot find it now, but a documentation of this exists with schematics and description and build/troubleshooting instructions  ...and maybe even videos. I remember that it was an innovative combination of the TL494 PWN Ctrl and the 74HC4046 PLL that was never published on the Internet before.
I have done this project in collaboration with Itsu so maybe he can send you a link to it. He has my consent to publish this. He is a much better record keeper than I am ;)
   

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In my opinion, while replicating these type of devices, the coil (or transformer) construction is very critical (including insulation material of the wire), so I applaud your decision to replicate this component as close as possible to the original.


However, signal generating circuits are not critical at all, when the target waveform is known. In fact, most of their functionality can be replicated with your FG alone (minus the high power components). Bursts of multiple pulses (почки импульсов) are a piece of cake for your FG at any frequency ...up to its rating.
In my opinion, the signal generating portion can even be improved by using automatic phase tracking techniques like we once did by combining the TL494 with the 74HC4046 PLL.

Thanks,  4mm² wire will arrive tomorrow.

For the pushpull/synchronizer, it is a simple setup which anyone would be able to build and use, so i think it is important to show it can do all it claims. 

The PLL system you mention was presented on this forum here:
https://www.overunityresearch.com/index.php?topic=3472.msg62527#msg62527
It includes a diagram and video.

It will be very usefull lateron to further stabilize the series resonance of this system.

Regards Itsu 
   

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If that 613kHz signal feeds a low reactance coil, then this 20Vp-p signal from the 50Ω FG would be loaded down to millivolts.  Measure the voltage amplitude across this coil to see if it is a problem.
If that is a problem, then the solution to this would be your EL2009 low impedance follower. It works down to DC ...and protects the FG's output, too.

Using my EL2009 protection box as buffer/amplifier for my FG (another great circuit design by verpies, see:  https://www.overunityresearch.com/index.php?topic=3388.msg59117#msg59117)
i pumped up my FG input into the grenade to allow more signals to be seen by my SA, but there are not much more signals, only stronger, see screenshot.

Itsu
   

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The PLL system you mention was presented on this forum here:
https://www.overunityresearch.com/index.php?topic=3472.msg62527#msg62527
It includes a diagram and video.
It should be mentioned that the R15, R16, R17, R18, R19 R20 should be high-precision resistors and RV4 should be adjusted so the waveform on the TL494.pin5 is exactly the same as when the TL494 is operating alone in its STANDARD application note straight from its datasheet.
I also remember that the v & i comparators made with U2a and U2b are configured with hysteresis (adjustable by RV1 and RV2) in order to handle variable amplitude noisy analog signals and to convert them to simple digital rectangular pulses on pins 3 and 14 of the 74HC4046. 

However, hysteresis introduces inherent phase shifts of its own, so more effort should be put into improving these i & v comparators in order to eliminate these phase shifts ...but that is nothing difficult or exotic.
If anyone here has a good idea how to improve them easily, please share it.
   

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i pumped up my FG input into the grenade to allow more signals to be seen by my SA, but there are not much more signals, only stronger, see screenshot.
If  new peaks had appeared on your spectrograms, I would be worried that the EL2009 follower is introducing its own harmonics/distortions.  So it is excellent news, that you are not seeing any new peaks ...just stronger ones.  Do you know their current amplitude ?
With the EL2009, your FG is a lot safer now, too.
« Last Edit: 2021-04-18, 21:28:48 by verpies »
   

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It should be mentioned that the R15, R16, R17, R18, R19 R20 should be high-precision resistors and RV4 should be adjusted so the waveform on the TL494.pin5 is exactly the same as when the TL494 is operating alone in its STANDARD application note straight from its datasheet.
I also remember that the v & i comparators made with U2a and U2b are configured with hysteresis (adjustable by RV1 and RV2) in order to handle variable amplitude noisy analog signals and to convert them to simple digital rectangular pulses on pins 3 and 14 of the 74HC4046. 

However, hysteresis introduces inherent phase shifts of its own, so more effort should be put into improving these i & v comparators in order to eliminate these phase shifts ...but that is nothing difficult or exotic.
If anyone here has a good idea how to improve them easily, please share it.
Hi verpies I'm getting an error for that pointer says it's off limits or lost, any chance if you can re publish it for referance? many thanks SIL
   

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Hi verpies I'm getting an error for that pointer says it's off limits or lost, any chance if you can re publish it for refgerance? many thanks SIL
I am not the owner of that thread.  I don't have the rights to set its access permissions.
   
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