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Author Topic: Itsu's workbench / placeholder.  (Read 105209 times)

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green is the current, using my current probe, throught L2,
What is that HF burst on the falling edge, before the negative peak, in the 2nd time division?  Do your sims show it, too?

yellow is the voltage across a 1 Ohm 1% induction free csr in the L3 to bridge lead.
Doesn't that current go slightly negative in the 3rd time division?  The green one does not do that...
   

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What is that HF burst on the falling edge, before the negative peak, in the 2nd time division?  Do your sims show it, too?
Doesn't that current go slightly negative in the 3rd time division?  The green one does not do that...

no, the sim does not show the HF burst, but the sim has more things that don't mach, its over the whole much more cleaner in signals, see screenshot.

Hmmm,  the yellow current in he 3th division is more straight (following the zero line), the green current goes below its zero line there (negative).

     
   
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Hi Nelson,

doing well,   thanks.

This circuit "acts" more like a step up boost converter to me giving it steps up the 24V input voltage to 450V (my replication).

How this one works exactly hopefully can be explained by others, but in general, see:
https://en.wikipedia.org/wiki/Boost_converter.

Regards Itsu


Hi Itsu ,
I’m not totally full agree with you about the circuit acting like step up boost converter, only .. :)

In some of the measurements you already did , we see an increase in current output vs input , but i understand your logic to consider the circuit like a booster , because when output is unload , show a much higher voltage then the input (450v) , but it is true when you connect a low impedance load at output the current increase and voltage lower. Buck or boost converter ? :)
At 24V on the input , the C4 and C5 capacitor have a variation , with a high peak of current and voltage , and that should the reason to be induced in L2/L3 CMC  the high voltage in output , even being wired in a 1:1 ratio .
The configuration of L2/L3 not allow a step up or step down like a conventional transformer.
Well , I think we have some aspects yet to understand .

Many thanks Itsu



---------------------------
Best Rewards
Nelson Rocha

" The goal is not to be successful, the goal is to be valuable.
Once you’re valuable, instead of chasing success,
it will attract itself to you. "
   
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Posts: 114


Buy me a drink
Hi Nelson,

doing well,   thanks.

This circuit "acts" more like a step up boost converter to me giving it steps up the 24V input voltage to 450V (my replication).

How this one works exactly hopefully can be explained by others, but in general, see:
https://en.wikipedia.org/wiki/Boost_converter.

Regards Itsu



Hi Verpies ,

I will you answer later based in the updates brought by Itsu.
Many thanks




---------------------------
Best Rewards
Nelson Rocha

" The goal is not to be successful, the goal is to be valuable.
Once you’re valuable, instead of chasing success,
it will attract itself to you. "
   

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Hi Itsu ,
I’m not totally full agree with you about the circuit acting like step up boost converter, only .. :)

In some of the measurements you already did , we see an increase in current output vs input , but i understand your logic to consider the circuit like a booster , because when output is unload , show a much higher voltage then the input (450v) , but it is true when you connect a low impedance load at output the current increase and voltage lower. Buck or boost converter ? :)
At 24V on the input , the C4 and C5 capacitor have a variation , with a high peak of current and voltage , and that should the reason to be induced in L2/L3 CMC  the high voltage in output , even being wired in a 1:1 ratio .
The configuration of L2/L3 not allow a step up or step down like a conventional transformer.
Well , I think we have some aspects yet to understand .

Many thanks Itsu

Nelson,

voltage boost or buck, current boost or buck, it indeed depends how you look at it.
Below graps show the relation between input versus ouput voltage and input versus ouput current.

The values do cross, but in the end what matters is the Power in versus out, which do no cross.

regards Itsu
   

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I will you answer later based in the updates brought by Itsu.
I really would rather lurk now
   

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Here a zoomed in (1 cycle) screenshot of the currents through T1 (L2 green and L3 yellow).
Yellow (L3) NOT inverted now.

The HF bursts are 2.2MHz.

Itsu 
   
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Nelson,

voltage boost or buck, current boost or buck, it indeed depends how you look at it.
Below graps show the relation between input versus ouput voltage and input versus ouput current.

The values do cross, but in the end what matters is the Power in versus out, which do no cross.

regards Itsu

Hi Itsu ,
I understand your point of view when you say that what matters is the Power in vs out .
Thanks by your opinion.



---------------------------
Best Rewards
Nelson Rocha

" The goal is not to be successful, the goal is to be valuable.
Once you’re valuable, instead of chasing success,
it will attract itself to you. "
   
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Posts: 114


Buy me a drink
I really would rather lurk now

Hi Verpies ,

I just told you that i would answer later, because of your question, regarding if inducing and induced currents flow through SMC at the same time, and I only saw Itsu's reply later, confirming this point, with their scope shots .

But thanks anyway.




---------------------------
Best Rewards
Nelson Rocha

" The goal is not to be successful, the goal is to be valuable.
Once you’re valuable, instead of chasing success,
it will attract itself to you. "
   
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Itsu,

I see you are using your new MDO3034 scope! How do you like it?

Regards,
Pm
   

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The HF bursts are 2.2MHz.
Could the step recovery of a diode be responsible for this?
   

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Itsu,

I see you are using your new MDO3034 scope! How do you like it?

Regards,
Pm

Hi Partzman,   well noticed,   yes,  using the MDO3054 now mostly, its a very nice piece of equipment.

I like the pushbuttons to quickly center the signals and all the build in / on board goodies like the pre settings for my AM503B / A6302 current probe (deskew).

Still working my way around all the settings, but really love it.

Itsu
   

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Could the step recovery of a diode be responsible for this?

verpies,

i would have thought that those modern UF4007 (2) would have a small distinct PN junction which would not allow or minimize these sharp pulses caused by it.

Perhaps i can swap them for some KD206D diodes which are known for their fuzzy PN junction and see if those HF pulses increase.

Itsu   
   

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Hi Nelson,

what are your feelings about your circuit?
Do you feel we did enough to analyze it, or do you think there needs to be done more to understand it?

Unfortunately i can not further help you in understanding how it does what it does.
I have tried to give as much details on the tests i did on my replication and gave the results as clear as i could in data and graphs.
   
If there is anything you can come up with which we can test, please tell me so i can give it a try.


Do you have any other intriging circuits you want to share with us so we can replicate and test it?

My favourite to replicate would be your "amazing oscilator" which i still have the video of, the one you start with a piezo lighter and carry around through your house.

Take care,   regards   Itsu
   
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Hi Nelson,

what are your feelings about your circuit?
Do you feel we did enough to analyze it, or do you think there needs to be done more to understand it?

Unfortunately i can not further help you in understanding how it does what it does.
I have tried to give as much details on the tests i did on my replication and gave the results as clear as i could in data and graphs.
   
If there is anything you can come up with which we can test, please tell me so i can give it a try.


Do you have any other intriging circuits you want to share with us so we can replicate and test it?

My favourite to replicate would be your "amazing oscilator" which i still have the video of, the one you start with a piezo lighter and carry around through your house.

Take care,   regards   Itsu

Hi Itsu,

At this moment, despite all the tests that have been conducted, it is not completely clear to me about some points that were observed, however I get the impression, that this feeling is partly reciprocal, at least I got this idea.

As you mentioned that you can't help anymore understanding how it does what it does, I am still very grateful for your collaboration and by Gyula, sincerely , but I will continue to try to understand some less clear points for me, such as the negative variations of voltage and current verified, as well  another aspect regarding the fact that the transformer is 1:1 and exhibits a deviated behavior, of the Mutual induction process, exhibited by a common transformer.

About "amazing oscillator" I sold the rights off this small circuit, a few years ago to a South Korean company, which earned me a small sum of money that today I would not have sold, at least for the amount I sold at that time.
I have no way of knowing, accurate information, and circuit details since I was hacked,  most of the information in my netbook like circuits videos , thoughts and diagrams  was stolen and deleted, even on social channels like youtube.

Could you provide me with that same video to integrate into my library?
I would be very grateful for that.
I have been trying to recover some of the videos I missed, because, in some way, they are a "consolation" for all the real circuits that were "confiscated" from me.
I'm starting a new topic on the OU related to one of my old circuits with pancake coils, I would be delighted, that whenever you wanted to give your opinion or even participate when you have time and availability .
once again, thank you very much for your help and participation in this circuit, as well as Gyula's help.



---------------------------
Best Rewards
Nelson Rocha

" The goal is not to be successful, the goal is to be valuable.
Once you’re valuable, instead of chasing success,
it will attract itself to you. "
   

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Nelson,

i also am unclear about what i see at certain points in this circuit, but i lack the knowledge to explain them, so yes that feeling you have is reciprocal.


Concerning the "amazing oscillator",   thanks for the info.

I can send you that video, no problem, just give a valid Email address using mine (see my profile here).
Hopefully the 14.4MB is not to much to send via Email.


I will be following your new topic and participate if possible.

Regards Itsu
   
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Nelson,

i also am unclear about what i see at certain points in this circuit, but i lack the knowledge to explain them, so yes that feeling you have is reciprocal.


Concerning the "amazing oscillator",   thanks for the info.

I can send you that video, no problem, just give a valid Email address using mine (see my profile here).
Hopefully the 14.4MB is not to much to send via Email.


I will be following your new topic and participate if possible.

Regards Itsu

Hi Itsu,
As I told you earlier, I am grateful for everything you have done.
I just want to leave this video to understand what I was referring to a few posts ago about apparent feedback for the power supply.
https://photos.app.goo.gl/ZMpr9ngb8wTNRpya8
I will send you my email, if it is not possible I will try to find an alternative, like sharing a space on Gdrive where you can place the video.



---------------------------
Best Rewards
Nelson Rocha

" The goal is not to be successful, the goal is to be valuable.
Once you’re valuable, instead of chasing success,
it will attract itself to you. "
   

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Hi Nelson,

i managed to send out the video via my Email, so you should have it by now.


Concerning your new above video, it made me smile as i wonder how on earth you come up with such things to try.  :)

You must have a very curious mind to try out all these things.  O0

I can try to replicate, and probably will get similar results, but to explain them in details i can not.

But generally i think it will boil down to the fact that you have an oscillator / transmitter that will send out a strong 17KHz signal which will influence all surrounded wirings and even goes into your PSU.

That PSU seems to be a dual PS one which probably internally is hooked up to each other so you can put the outputs in series or parallel etc.
With other words, the 17KHz RF will penetrate it and influences the internals to give (false) readings.

Also the output led bulb will light due to these 17Khz RF signals i am sure.

You might want to filter more strongly your primary power source by a CMC and some caps (electrolytic and ceramics) to see if these internal interactions go away.

I will do some replications and see if my dual PSU shows the same.


Regards Itsu
   
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Hi Nelson,

I agree with Itsu.  The AC output of the oscillator goes back to the PSU when you connect the LED or the wire back to the positive supply input.  Even if the L2/L3 coils as a 1:1 transformer isolates the output from the input, their stray inductance-capacitance may let some energy through.

You could check this by your oscilloscope which fortunately can operate from its battery i.e. ground independent.  Connect the scope probe croco gnd clip to the negative input supply rail and the tip of the probe to the positive input supply rail and see whether any 17 kHz or so AC signal appears or not across the rails when you loop back the AC output to the positive rail. 
Most likely you will see the AC component appearing across the rails.  When you connected the AC output behind the series input diode and you still had the "problem",  it is possible the diode remained forward biased from the supply input (i.e. the AC component had not enough current to influence its forward conduction).

One more thing:  what if you reduce the 0.3 V DC setting on your PSU's 2nd output to zero? will the near 1 A "load" current also manifest?

Gyula
   

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I did some similar tests as Nelson did but was unable to light up a similar led bulb (3.6W 240V).

But the feedback lead from positive L3 to the plus input lead (diodes in place) showed we got some extra input current (using the current probe) signals generated on this plus input lead.

It caused my PS display to show 1V less (from 17V to 16V) and its current display dropped from 30mA to 20mA
Also the current DMM in the input lead dropped from 30mA to 17mA, but the scope current probe showed an increase in rms current from 30mA to 45mA.

I tend to believe the scope to give the accurate current readings and not the DMM or PS display.

My second PS (set to 0.3V) did not change or got influenced by this feedback signal.

Video here: https://www.youtube.com/watch?v=9ReXhKLRoHo&feature=youtu.be

So yes there is RF feedback into the PS which influences the PS displays and DMM.

Regards Itsu
« Last Edit: 2020-05-27, 10:28:17 by Itsu »
   
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Hi Nelson,

i managed to send out the video via my Email, so you should have it by now.


Concerning your new above video, it made me smile as i wonder how on earth you come up with such things to try.  :)

You must have a very curious mind to try out all these things.  O0

I can try to replicate, and probably will get similar results, but to explain them in details i can not.

But generally i think it will boil down to the fact that you have an oscillator / transmitter that will send out a strong 17KHz signal which will influence all surrounded wirings and even goes into your PSU.

That PSU seems to be a dual PS one which probably internally is hooked up to each other so you can put the outputs in series or parallel etc.
With other words, the 17KHz RF will penetrate it and influences the internals to give (false) readings.

Also the output led bulb will light due to these 17Khz RF signals i am sure.

You might want to filter more strongly your primary power source by a CMC and some caps (electrolytic and ceramics) to see if these internal interactions go away.

I will do some replications and see if my dual PSU shows the same.


Regards Itsu

Hi Itsu ,
Thank you, I consider it a compliment :)
Sometimes in the irrationality of our mind, it can lead us to the strangest things you can imagine.
As soon as I have the opportunity, I will follow your advice and that of Gyula, I will try to test with your suggestions.

Many thanks



---------------------------
Best Rewards
Nelson Rocha

" The goal is not to be successful, the goal is to be valuable.
Once you’re valuable, instead of chasing success,
it will attract itself to you. "
   

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Hi Nelson,


take your time, i know you are a busy familyman and now especially with your thread on OU.com.


I have updated my above post with a video of my tests showing the RF feedback into my PS.

You can see there is negative current (going into the PS).
Not sure the scope rms value is correct (45mA) or the current DMM and PS current meter (17mA), but it think the scope, comments anyone  please!


The video is a little chaotic at times, sorry for that.

Regards Itsu
   
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Hi Nelson,

I have to make a small correction to my previous mail. I considered that it was the AC output what you connected back to the positive input rail but watching your video again it is clear you connected the positive DC output of the diode bridge to the positive input rail.
Only the scope probe was hooked up to the AC input of the diode bridge.

Even so, all the rest of my comments I wrote are still valid. 
The (nearly) 100 nF puffer cap which must be the yellow colored, rectangular capacitor under the diode bridge) can only filter the rectified DC coming from the diode bridge to a certain degree, so there should remain AC components superposed onto the DC voltage level, depending on the load.
I suggest to check the waveform across the DC output too by the scope, both when only the LED bulb is the load and also when you connect the positive output back to the positive input rail directly by the lead wire (red croco).

At video time 6:45 you activated the 12V incandescent bulb across the output while the positive DC output was directly connected back to the positive input rail and the 1 A current displayed on the power supply disappeared.
I think this clearly means the AC component across the DC output of the oscillator has diminished to a low value, not enough to cause the "problem"  (the scope measured only 64V pp across L3, instead of the 250V pp or so without the loading effect of the 12V bulb). 

Greetings
Gyula
   
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Hi Itsu,

IF you use the Fluke meter for measuring the input current instead of the M890G meter, would the 17 mA displayed current on it change?
 
I suspect that when you connect the output back to the DC input (either behind or in front of the diode), the input current waveform changes so much that the M890G DMM and also the internal meter of the PS displays a different value. 
We may trust better in the scope current probe I think.

Gyula
   

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Hi Gyula,

i quickly used my old Fluke 8060A true RMS DMM instead, and it showed the same behaviour as with the cheapo M890G DMM.

But when using the newer Fluke 179 true RMS DMM, i get NO change in the current AND no change in the PS voltage or current readings! (no change means a few tenth of mA's, like 29.4 without and 29.7 with).

It seems the newer Fluke filters out the RF going into the PS.

I will take some scope measurements tonight to see how this Fluke meter influences the RF feedback.

Thanks,   Itsu
« Last Edit: 2020-05-27, 14:18:04 by Itsu »
   
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