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Author Topic: Dally, Shark & Ruslan workbench  (Read 53574 times)

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If you'd like to know how this contraption is supposed to work, I would suggest that you read all the pdfs that Vasik has been nice enough to provide.
They don't answer this question directly. Besides, I understand Russian in native videos.

No need to insult me. I am only offering my opinion.
Not mincing words is not insulting to people of sturdy constitution.  I want your arguments, not you opinions which are unsupported by them.
Also, I expect a direct answer from you (and anyone else) to every sentence of mine that ends with a question mark.
According to my personal rules, not answering questions directly is disengaging and disrespectful and if done repeatedly - insulting. 

Or are you really worried about burning up a cheap transistor, by providing it with the maximum allowed voltages at it's base. Really?
Approaching or exceeding the Maximum Allowable VBE not only risks damaging the BJT but also precludes it from operating in the linear mode. The latter is of larger concern if the GLA hypothesis is correct.
« Last Edit: 2021-06-14, 01:58:30 by verpies »
   

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   Verpies:
   I'm not here to argue with you. Nor did I know that you can understand Russian. Good for you.
If my "opinions" are not enough for you, and you want arguments, instead,  I'm not sure that I have any further arguments to discuss.
If this is all about a volt or two, then have it your way, sorry for the false advice. In any case, it was meant for Itsu, assuming the data sheet is correct.
I did mention about the base voltages, "up to 5v".  And yes, my Kacher's base voltage is working as it should, and has sufficient output. If that is what you were asking. Same transistor on it for quite a while, and I have a few more of those 2SC5200, just in case. So, I'm not too worried about it, but thanks anyway, for your concern. However, I am pretty sure that is what is wrong with Itsu's Kacher output, which is the purpose of my comments.

   NickZ
   

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  Itsu:
   I have had that problem. If your transistor base is not getting the 5v emmiter base voltage, then you are not going to get the needed results.
   So, try to get the 5v on there, and it should work. Like Vasik mentioned, the higher the base voltage, the higher is the output, up to 5 volts.
   I'm glad it's not me going through all this. And, I doubt that the antenna signal has anything to do with it. 
   I did not design it either, but have spent much time behind the wheel.
   NickZ

Nick,

remember i have been there before too, i have build transistor and MOSFET kacher drivers and they worked in that they produced streamers and could light up fluor lamps etc.

But the real effect we were after did not manifest, so something must be missing.


So now i want to follow carefully some designs from Stalker from which i believe could produce the effect we are after.

And if that means to follow circuits i do not fully understand, so be it as with the help of the knowledgeable people here we should be able to crack it, but only by doing little steps and trying to understand the why and how which takes time.

Itsu
   

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Something else in this area what could be of concern is the alternative value's of R17 and R18 (the transistor base divider resistors).

They are shown in the below diagram as 740 Ohm (R17) and 350 Ohm (R18), and the text in the rk_rev2.pdf / video mentions something about putting the kacher in continues mode with them.

Surely they will cause a different base voltage and allow for more base current to flow, but i am not sure why they are mentioned there, perhaps as some test mode?

Itsu   
   

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They are shown in the below diagram as 740 Ohm (R17) and 350 Ohm (R18), and the text in the rk_rev2.pdf / video mentions something about putting the kacher in continues mode with them.
The continuous mode might mean, that the BJT is not amplifying periodically.
I think that tying the tc point to +12V might be called the continuous mode.  ...and yes, I think it is for test/tuning purposes.

Something else in this area what could be of concern is the alternative value's of R17 and R18 (the transistor base divider resistors).
These are the base biasing resistors. They set the transistor's operating regime. 
It seems, the author was searching for the best operating point of this transistor and was experimenting with different resistor values.

It would be interesting to find out what values of R17/R18 give you the best linear amplification of Q6 using the blue test setup depicted below, while scoping the amplitude at the collector.  The green signal is from the FG instead from the antenna.

   

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And yes, my Kacher's base voltage is working as it should, and has sufficient output.
You are assuming that the strong Kacher's output immediately means "working".  That does not have to be the case.

Modulating the Katcher's primary current at kHz frequencies is not the same as modulating it with kHz + MHz frequencies.
The Kacher's output can be strong with the BJT modulating its collector current at kHz frequencies only, while completely disregarding the MHz feedback from the antenna.

In the past, Itsu pulsed the Kacher at kHz frequencies without the MHz feedback from the antenna and he obtained a strong output out of it ...but that was only a conventional response of that circuit:

remember i have been there before too, i have build transistor and MOSFET kacher drivers and they worked in that they produced streamers and could light up fluor lamps etc.

But the real effect we were after did not manifest, so something must be missing.
   

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The continuous mode might mean, that the BJT is not amplifying periodically.
I think that tying the tc point to +12V might be called the continuous mode.
These are the base biasing resistors. They set the transistor's operating regime. 
It seems, the author was searching for the best operating point of this transistor and was experimenting with different resistor values.

It would be interesting to find out what values give you the best linear amplification of Q6 using the blue test setup depicted below, while scoping the amplitude at the collector.  The green signal is from the FG instead from the antenna.
That circuit isnt mnuch different to the Akula circuit but it had a self oscillating output stsge (another night mare) so i'm verry interested how your going to get any activity in the Mhz region.

Regards SIL
   

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...I'm verry interested how your going to get any activity in the Mhz region.
These coils ring in the MHz region after being pulsed.  The BJT can linearly amplify that oscillation when biased properly because its base is connected to these coils/antenna.
   

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Well yes the ringing bit's true so it might be worth re looking at that PCB (it's a bit blurred in colour).
It would be interesting to know what frequency your driving that circuit with and have you a scope shot
of any of the stages and the Audio output transistor collector you can post would be nice.

Regards SIL
   

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Something else in this area what could be of concern is the alternative value's of R17 and R18 (the transistor base divider resistors).

They are shown in the below diagram as 740 Ohm (R17) and 350 Ohm (R18), and the text in the rk_rev2.pdf / video mentions something about putting the kacher in continues mode with them.

Surely they will cause a different base voltage and allow for more base current to flow, but i am not sure why they are mentioned there, perhaps as some test mode?


Itsu,

I understood it in a way that 740Ohm and 350Ohm used for some other application, like a power switch, not kacher.
Have you tried appling more than 24v power to the circuit ? It could be that 24v is to small, it is supposed to work from significant higher voltage (50-150v).

Vasik


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I understood it in a way that 740Ohm and 350Ohm used for some other application, like a power switch, not kacher.
The ratio of these resistors sets the base voltage bias of the BJT...and consequently its operating point with respect to AC signals appearing at its base.
The magnitude of these resistors determine the Thevenin resistance of the voltage divider formed by them.  The lower this resistance, the higher the attenuation of the AC signal being applied to the base.

@Vasik041:  Of course, you knew all that.
   

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Itsu,

I understood it in a way that 740Ohm and 350Ohm used for some other application, like a power switch, not kacher.
Have you tried appling more than 24v power to the circuit ? It could be that 24v is to small, it is supposed to work from significant higher voltage (50-150v).

Vasik


   Vasik: Well, that's good to know, and you may be right about that.
So, why not just adjust the base voltage to the right values, (less than the 5v max), but close to it? As the 500mV is just not right.

   Verpies:  I am not assuming that because my Kacher circuit is working properly, that the sync between it and the induction circuit is also. 
Both the induction circuit, and the Kacher are working well by themselves, but still not producing the OU needed, nor the desired results.
What may be missing or just plain wrong in the diagrams and schematics has been part of the on going riddle, making for more problems to solve.
   

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The ratio of these resistors sets the base voltage bias of the BJT...and consequently its operating point with respect to AC signals appearing at its base.
The magnitude of these resistors determine the Thevenin resistance of the voltage divider formed by them.  The lower this resistance, the higher the attenuation of the AC signal being applied to the base.

@Vasik041:  Of course, you knew all that.
Yes that’s a class A slope amplifier that’s associated with single ended amplifiers and usually draws a load of current too.

It's also used in old valve AM modulation TX circuits that broadcasts both audio and digital and self oscillating tuned output pentodes so will
some one be adding a staked totem poled output stage later ? 

https://www.circuitstoday.com/class-a-power-amplifiers

PS I wonder if Nick has worked out what the centre slope current might expect to see ? as any input would help us all.

Regards SIL


   
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IMO, there is considerable confusion regarding the 2SC5200 bipolar transistor. 

Please look at the data sheet for this device and in the maximum ratings, Vebo = 5v max. This is not Vbe the forward base/emitter voltage, but rather Vebo which is the maximum reverse emitter/base voltage.  What this means is that the emitter/base junction, if subjected to a reverse voltage of no more than 5v, will be guaranteed not to avalanche.  This has nothing to do with the normal operating forward voltage of the base/emitter junction.  There is no way that the forward voltage of this device or any NPN power device or small signal device could reach 5v without complete destruction of the junction.

In the electrical characteristics for this device, we see the maximum operating Vbe at 7 amp collector current is 1.5v with a typical value of 1v.

Now, as to the operation of the circuit, there are only three modes that the 2SC5200 can be operating in not counting on/off switching.  These would be class A, some form of B, or C. 

In class A, the base is biased in such a manner that the dc quiescent point would be positioned at the midpoint in the collector load line.  This mode normally allows for symmetrical clipping of the loaded collector.

In class B and all it's variations, the base bias is reduced so the device normally operates as a unipolar device regarding the AC signal.  This type of operation is usually seen in totem pole style power output stages.

Class C operates with zero or negative base bias and again in a unipolar mode.

The Stalker circuit with the 2SC5200 base shunt and series resistors is the absolute worst design possible for hard switching of the device IMO.  Therefore, I agree with Verpies that more than likely the device is meant to be biased in either class A or one of the B modes.  If this is the case, I can see why there would be difficulty is achieving consistent results because of the base biasing scheme used.  The large signal beta or HFE of these devices will vary across a lot such that with no emitter resistive feedback network, the base resistors will have to be experimentally determined and selected for each device used.  Again, a poor design because this gain will vary with temperature which will be like hitting a moving target with the present base biasing scheme!

Evidence of this device operating in particularly class A would be the requirement of a large heatsink perhaps with cooling.  It could be operating in class B with less bias which would lower the device dissipation and therefore the cooling requirements.

Therefore IMO, it would be most important to determine the operation of the overall circuit and how it would achieve gain.

Regards,
Pm 

   

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This is not Vbe the forward base/emitter voltage, but rather Vebo which is the maximum reverse emitter/base voltage. 
You're right - typical VBE is much lower.
I skimmed the datasheet and took Nick's word for granted when he wrote that he has 5V on the base.
Now, I am even more amazed how his transistor remains functional.

Evidence of this device operating in particularly class A would be the requirement of a large heatsink perhaps with cooling.
I think Itsu has it on a heatsink.
   

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Great,  this is what i am talking about,    knowledgeable people putting their heads together to crack this puzzle.

Yes, there is a cooled heatsink on the transistor.

Lots of great suggestions, so i will try to put 150V on the collector with the present 8.2K R17 resistor.

I will also try to follow verpies his suggestion in post #904, but i need to make both R17 and R18 variable somehow.
Guess 100K trimmer pots parallel to them could do it.

Thanks all,   Itsu 
   

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Guess 100K trimmer pots parallel to them could do it.
If you tweak it all the way down to 0Ω then magic smoke will escape.
So put some safe resistances in series to prevent excessive currents ...and remember, that the 2SC5200 base cannot take more than 1.5A, too.
   

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  Verpies:
   Ok, did I say that I have 5v on the base? No, I may have less than that, but I know that for my device, it works, even though I may run it hot without the fan on. I get enough streamer to do what it supposed to do. But, it doesn't provide for OU, as it's supposed to.
Are you really worried about my transistors? So then, what should the bias voltage be at the 2SC5200 base???  What is the max base voltage? As the 500mV is obviously, not high enough, at lower inputs.  Or is this another riddle?
   

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Ok, did I say that I have 5v on the base?

No but you wrote:
If your transistor base is not getting the 5V emitter base voltage, then you are not going to get the needed results.

Are you really worried about my transistors?
Yes but my main concern is that at 5V base bias voltage, the BJT is not functioning as class A or B amplifier.

So then, what should the bias voltage be at the 2SC5200 base???  What is the max base voltage?
The maximum base emitter voltage is such that it does not cause more than 1.5A to flow into the base.
This varies from transistor to transistor because of the variances in the manufacturing process and temperature and collector-emitter voltage and collector current.

https://www.researchgate.net/profile/Donggyu-Jang-2/post/Why_is_base-emitter_voltage_in_transistor_always_assumed_as_06_V/attachment/59d621fe6cda7b8083a1b7c8/AS%3A273800879378432%401442290624299/download/BJT+base+current+vesus+base+emitter+voltage.jpg
Dally, Shark & Ruslan workbench


However, your asking me this question suggests that you still think that more base voltage is better, which indicates that you keep missing my point. 

If the goal is to amplify the AC signal from the antenna as much as possible then the optimum base bias needs to be determined experimentally by adjusting it for the highest amplitude at the collector, like I described in post #904.

In class A, the base is biased in such a manner that the dc quiescent point would be positioned at the midpoint in the collector load line.  This mode normally allows for symmetrical clipping of the loaded collector.

Hopefully Itsu will make a nice video that will show Nick how the output amplitude initially increases and subsequently decreases as the base bias is increased past the midpoint of the collector load line and the signal is clipped.

Or is this another riddle?
What was the previous riddle you imply in that question ?
   

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  The previous riddle is why are we following a diagram or schematic that is showing the wrong bias resistors for our set up.
However, that is not my same set up. I am watching what Itsu is coming up with for his current efforts. And yes, there is some confusion about what should then be the proper resistance for the base bias. At least,  there is some confusion, for me. Yet, my Kacher works, and has enough output. But, the proper sync is another story. I did test my base voltage experimentally. Yet, there are other components that are also at work here, such as the input choke.

   Verpies: You mentioned: "Hopefully Itsu will make a nice video that will show Nick how the output amplitude initially increases and subsequently decreases as the base bias is increased past the midpoint of the collector load line and the signal is clipped".
                                                                                                                                                end quote.

   That would be nice. As well as to show me the interaction, between that test, and the induction circuit/grenade output.
Like I said,  holding my breath. I really do want to see this work, as planned.

   NickZ

   Partzman:  Thanks for the input.
   

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Itsu,

I am trying to understand the issue. I think you got kacher working at some point (few weeks ago). What happened after that ?

Do you have components marked with blue pen in your setup ?

Vasik


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Kasik041
I have seen those forms countless times and it's just signal modulation.

The first time I saw it was when building the Adams motor. The magnet on the rotor induces a clean sine wave on the stator coil which is then interrupted by a transistor running at high frequency. Thus the product is a high frequency embedded within a sine or other wave form like the pictures you posted. As I continued by experiments I found that any number of discrete frequencies can be injected into the main wave form.

At which point were verging into TPU territory whereby a two phase shifted frequencies could produce a travelling wave upon a conventional sine wave. Here it's important to understand the the concept of "Energy". Energy is motion, Energy is change and whenever there is more change there is more energy present.

Regards
AC

There are known knowns; there are things we know that we know.
There are known unknowns: that is to say, there are things that we now know we don't know.
But there are also unknown unknowns; there are things we do not know we don't know.



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

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Itsu,

I am trying to understand the issue. I think you got kacher working at some point (few weeks ago). What happened after that ?

Do you have components marked with blue pen in your setup ?

Vasik

Vasik,

Quote
I am trying to understand the issue. I think you got kacher working at some point (few weeks ago). What happened after that ?

i was wondering that myself, but it was kind of working here: https://www.overunityresearch.com/index.php?topic=3926.msg92612#msg92612

After that i measured the collector current in continuous mode and found it to be to high at 428mA @ 12V.

So i adjusted the R17 (3.3K) to have a collector current of 150mA which was with a 8.2K resistor.

Since then i have almost no power out on the kacher with either 12 or 24V, see https://www.overunityresearch.com/index.php?topic=3926.msg92671#msg92671


Quote
Do you have components marked with blue pen in your setup ?


Both the 12 and 24V module PS's i now use have such circuitry at its outputs, not the same value's, but similar, like a CMC, ceramic cap, poly cap, electrolytic cap etc.


Itsu
   

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Itsu,

Quote
Since then i have almost no power out on the kacher with either 12 or 24V

You mean output power/voltage is small or kacher does not start at all ?

Vasik


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Well, like i mentioned here:

Quote
Since then i have almost no power out on the kacher with either 12 or 24V, see https://www.overunityresearch.com/index.php?topic=3926.msg92671#msg92671


where it says:

Anyway, after reinstalling all the chips etc. and firing up the kacher, the "umph" seems gone now from the kacher as the 12V PS for the primary coil shows no current and a NE-2 neon does not light up.
The scope probe near by does show some minimal activity (typical switched kacher ringing signal).


So kacher seems working, but at very low acivity.

Itsu
   
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