PopularFX
Home Help Search Login Register
Welcome,Guest. Please login or register.
2021-12-05, 05:30:07
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 ... 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 [38] 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 ... 104
Author Topic: Dally, Shark & Ruslan workbench  (Read 74895 times)

Hero Member
*****

Posts: 749
Well, like i mentioned here:

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

"umph" confuse me :)
You increased R17, this naturally lowered power.
Now you can carefully increase power supply voltage and look for radiant effects (DC on metallic surfaces, white sparks). This could sound strange, why not use 24v and lower R17, because... we are not really interested in power (or "umph" if that is correct word here). We are looking to create shock waves. This achieved by abrupt pulse bursts. We can't make pulses much sharper, so we rising supply voltage, so dV/dt will be higher.
This is how I understand logic behind this setup.

Vasik

PS if rising voltage will be not enough then you can try decrease slightly R17.

PPS Don't do like this https://youtu.be/63aANVr0kCM?t=41

 


---------------------------
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: 3270

Vasik,

sorry for the confusion, i will try to use more appropriate terms in the future  O0

I have a 24 to 150V DC2DC boost converter which i think i can use, just building the output filtering for it.

Meanwhile i will try to follow the other suggestions to measure the effect the biasing has on the output.


Itsu
   

Group: Moderator
Full Member
*****

Posts: 225
Enjoy your trek through life but leave no tracks
@ Vasic and Itsu could you please show your wave forms on the IR2110 pins 1 and 7 and the 2N5200 collector and base using a dummy load please

Note the base bias i get is between 0.2 and 0.4 volts using 20 khz on my test circuit if i go higher like 36 khz the Mos Fets start to round off the tops of the pulse wave.
I can possibly show some wave forms later on.

Regards Sil
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270
Setting up the below test environment, and trying to get into "continuous (non-pulsed) amplification, by forcing the tc point to +12V for this test, ...just like before", i again / still have NO pin 1 of the (now) IR2113 active while its pin 12 is on +12V.

It looks to me like how a MOSFET can be set ON or OFF and stay in that condition untill some thing is reset as when i reinstall U10 and pulse the IR2113 again, it works fine.

If not working i will have to remove the IR2113 instead and tie its pin 1 to +15V.......


Itsu
   
Sr. Member
****

Posts: 289
Setting up the below test environment, and trying to get into "continuous (non-pulsed) amplification, by forcing the tc point to +12V for this test, ...just like before", i again / still have NO pin 1 of the (now) IR2113 active while its pin 12 is on +12V.

It looks to me like how a MOSFET can be set ON or OFF and stay in that condition untill some thing is reset as when i reinstall U10 and pulse the IR2113 again, it works fine.

If not working i will have to remove the IR2113 instead and tie its pin 1 to +15V.......


Itsu

Itsu,

A suggestion...

Tie the junction of C26 and U10B pin 6 to VDD.  Adjust RV7 so there is at least a few K of resistance between its wiper and pin 3 of U10A.
Connect your FG output to pin 2 of J1 (and ground).  Set the FG so it outputs a zero to +12 logic level square wave (zero to +12V, not +/- 6V).  Connect one channel of the scope to the FG output (and trigger from this channel).  Connect two additional scope channels to HO and LO on the driver IC.

This will allow you to verify that the circuit is operating as intended at various frequencies down to DC .

PW
   

Group: Professor
Hero Member
*****

Posts: 2602
It looks to me like how a MOSFET can be set ON or OFF and stay in that condition until some thing is reset as when i reinstall U10 and pulse the IR2113 again, it works fine.
It's possible that one of your pins is floating and the voltmeter does not detect it. You can try powering down the circuit and checking for unexpected floating pins using an ohmmeter.

If not working i will have to remove the IR2113 instead and tie its pin 1 to +15V.......
If you do that, don't forget to tie its pin 7 to ground.
You don't want to have Q3 and Q4 on at the same time.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270
PW,

good suggestion, i can try that.



verpies,

pins 2, 5, 11 and 13 are tied to ground (0.2 Ohm)
pins 3 and 6 tied to +15V (measured)
pin 9 tied to +12V (measured)
rest is undetermined.

Itsu
   

Group: Professor
Hero Member
*****

Posts: 2602
pins 2, 5, 11 and 13 are tied to ground (0.2 Ohm)
pins 3 and 6 tied to +15V (measured)
pin 9 tied to +12V (measured)
rest is undetermined.
When you remove U5 do you tie IR2113 pin 12 to +12V and pin 10 to ground ?
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270
When you remove U10 do you tie pin 12 to +12V and pin 10 to ground ?

No,  just pin 12 (and 10 / 13) to +12V.

   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270
Ok,  no when removing U10 i do nothing with the IR2113.

I tie U10 pins 10, 12 and 13 to +12v, thats it.


I just now as an extra to the above tied down the IR2113 pin 10 to ground, but it does not get its pin 1 active nor do i see any collector current flowing.
   

Group: Professor
Hero Member
*****

Posts: 2602
When you remove U5 do you tie IR2113 pin 12 to +12V and pin 10 to ground ?
No,  just pin 12 (and 10 / 13) to +12V.
I was asking about the IR2113 pins and I meant after removing U5. (I was correcting it when you were already replying).
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270

Ok,  i never removed U5.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270

I can remove U5, but then via U10 we will still have a pulsed signal on IR2113 pin 12

So i removed U5, tied IR2113 pin 10 to ground, and we have a pulsed signal on IR2113 pin 1 (also without pin 10 to ground)
When in addition i tie up IR2113 pin 12 to +12V i have a solid +12V on IR2113 pin 1 (also without pin 10 to ground).
   
Sr. Member
****

Posts: 289
I can remove U5, but then via U10 we will still have a pulsed signal on IR2113 pin 12

So i removed U5, tied IR2113 pin 10 to ground, and we have a pulsed signal on IR2113 pin 1 (also without pin 10 to ground)
When in addition i tie up IR2113 pin 12 to +12V i have a solid +12V on IR2113 pin 1 (also without pin 10 to ground).

Itsu,

Be aware that if you remove U10, you will have no debounce on LIN, which could be problematic (not sure how 'touchy" the driver inputs are, just food for thought...).

PW
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270

PW,

not sure what you mean by debounce.

When U10 is removed and its pins 10, 12 and 13 are tied to +12V via a 1K resistor, also IR2113 pin 12 (LIN) via R7 is tied to +12V.
There should be no room for undetermined signals there.

Itsu
   
Sr. Member
****

Posts: 289
PW,

not sure what you mean by debounce.

When U10 is removed and its pins 10, 12 and 13 are tied to +12V via a 1K resistor, also IR2113 pin 12 (LIN) via R7 is tied to +12V.
There should be no room for undetermined signals there.

Itsu

Itsu,

I thought you were applying the 12V to LIN after powering up the driver. 

What happens at LO when you cycle LIN between 0V and 12V a few times? 

PW

 
   

Group: Professor
Hero Member
*****

Posts: 2602
I can remove U5, but then via U10 we will still have a pulsed signal on IR2113 pin 12
I meant to remove U5 in addition to U10.
I assume that removing these chips is easy because they are in sockets. If they are not then it is a bad idea to remove them.

So i removed U5, tied IR2113 pin 10 to ground, and we have a pulsed signal on IR2113 pin 1 (also without pin 10 to ground)
When in addition i tie up IR2113 pin 12 to +12V i have a solid +12V on IR2113 pin 1 (also without pin 10 to ground).
So it is behaving as expected.
U7.pin10 does not affect the output on U7.pin1.
U7.pin10 affects only the output on U7.pin7.
U7.pin12 affects only the output on U7.pin1.
U7.pin11 affects both U7.pin1 and U7.pin7 when it is tied to VCC.

Does it seem like when U7.pin10 is left floating then U7 treats it as low input signal? (perhaps due to some internal pull-down resistor or non-CMOS input).
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270
OK,   what i did up till now is power off the 24V to the PCB, remove U10 and install the 1K resistor between U10 pin 14 (+12V) and U10 pin 12 (10 and 13).
Then after power on the 24V to the PCB, there is +12V at IR2113 pin 12 (LIN), but 0V at IR2113 pin 1 (LO).


What i now did is power off the 24V to the PCB, remove U10 (not tie up its pin 12 to 12V yet) and power on 24V to the PCB.
It shows no 12V to IR2113 pin 12 (LIN) which is obvious and 0V to IR2113 pin 1 (LO) also obvious.

If we now connect +12V via a 1K resistor to U10 pin 12 (10 and 13) we see +12V to IR2113 pin 12 AND we now have +14.4V at IR2113 pin 1.

So it seems a timing problem within the IR2113 when it sees / checks for 12V on its pin 12 to act accordingly to activate pin 1.

Itsu
   

Group: Professor
Hero Member
*****

Posts: 2602
So it seems a timing problem within the IR2113 when it sees / checks for 12V on its pin 12 to act accordingly to activate pin 1.
There are these UnderVoltage (UV) lockout blocks and the SR Latches (circled in red) that can cause problems when the powerup sequence is wrong.
In this application, the pin11 (SD) is hardwired to ground so I doubt that it goes low after pin12 (LIN) or pin10 (HIN) ...and that takes the suspicion off these SR Latches.
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270

Now that i can activate the "continuous (non-pulsed) amplification", i used the present R17 (8.2K) / R18 (2.7K) bias setting to see what happens when a 5MHz sine wave signal (2Vpp) is injected to the base of the transistor via a 100nF capacitor while loading the collector with 100 Ohm @ 24V.

See below diagram.

Next is to make R17 and R18 variable to see what happens when varying the base bias.

Screenshot shows:
purple: FG input signal
blue: transistor base signal
yellow: transistor collector signal


Video here: https://youtu.be/bUWBt8hnxLs

Itsu
   

Group: Professor
Hero Member
*****

Posts: 2602
Looks like you have some linear amplification happening.
When doing this experiment, pay special attention to the ratio of amplitudes of the signal on the collector vs. the signal on the base. Your scopeshot shows approximately 16x gain, now.
As you vary the R17/R18 it might be easier to put the scope channel, which is connected to the collector, into the AC mode.

Also, if you view the collector signal on the SA you will be able to see when it starts distorting much earlier than on the scope. Of course, use an attenuator as not to overload the SA.

Do you remember whether the signal from the real antenna was also around 5MHz ?
« Last Edit: 2021-06-16, 00:35:08 by verpies »
   

Sr. Member
****

Posts: 350
  Well guys, first of all, I would like to give my thanks, and appreciation to Verpies, and to all others that are participating in these tests, and research.
  As well, as to Partzmann, for clearing up the confusion (for me), as to the 2SC5200 base voltage specs, as shown on the data sheets.
I am very thankful, for that.  As that is now also a very critical point, in Itsu's on going test and experiments, on just what is the best base voltage, and current to provide for optimum gain, of that particular transistor.
   Again, I am thankful for the tip, as I had no idea that providing up to the 5v, according to what I had thought previously, was NOT the best or correct voltage to provide to the base of that transistor. So, the question remains then... What is the best base voltage/current to provide for the highest gain on this interuptor signal/shock wave circuitry?
   
   NickZ
   
Sr. Member
****

Posts: 289
Now that i can activate the "continuous (non-pulsed) amplification", i used the present R17 (8.2K) / R18 (2.7K) bias setting to see what happens when a 5MHz sine wave signal (2Vpp) is injected to the base of the transistor via a 100nF capacitor while loading the collector with 100 Ohm @ 24V.

See below diagram.

Next is to make R17 and R18 variable to see what happens when varying the base bias.

Screenshot shows:
purple: FG input signal
blue: transistor base signal
yellow: transistor collector signal


Video here: https://youtu.be/bUWBt8hnxLs

Itsu

Itsu,

I thought the purpose of turning Q6 on continuously was to allow you to adjust the collector current to around 150ma.

If you are going to experiment with varying the Q6 base current, I suggest replacing R17 with a fixed 2K resistor in series with a 10K pot (R18 is a minor player, leave it at 2.7K).  This will allow you to vary the base current from approximately .9ma to 6.5ma.  Using the typical Hfe of 80, this will allow you to adjust collector current from 56ma to 520ma.  If you want higher collector current, reducing the fixed resistor from 2K to 1K will allow you to adjust between 80ma and 1amp of collector current.

To achieve collector currents much above above 200ma you will need to reduce the value of your 100R load resistor (or increase the 24 volt supply) 

All numbers and values are approximate, both Vbe and Hfe vary significantly with current and temperature (and between devices).  With no emitter degeneration, collector current will vary considerably as Q6's temperature varies.   

Q6 is a BJT, not a FET.  Base bias should be discussed in terms of base current, not base voltage.

It would be nice to know what and how this circuit is supposed to perform.  That being said, making adjustments using the FG and an arbitrary load may not equate to the desired operating parameters when connected to the rest of the circuit.

Again, I thought Vasik said to set the collector current to around 150ma, using the coil as a collector load and with 24V applied.

PW

 
« Last Edit: 2021-06-16, 04:55:24 by picowatt »
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270
Looks like you have some linear amplification happening.
When doing this experiment, pay special attention to the ratio of amplitudes of the signal on the collector vs. the signal on the base. Your scopeshot shows approximately 16x gain, now.
As you vary the R17/R18 it might be easier to put the scope channel, which is connected to the collector, into the AC mode.

Also, if you view the collector signal on the SA you will be able to see when it starts distorting much earlier than on the scope. Of course, use an attenuator as not to overload the SA.

Do you remember whether the signal from the real antenna was also around 5MHz ?

Yes, there is linear amplification already, so this could be the M.O. of this part of the device.

My present kacher / antenna frequency is about 1.2Mhz which also is a resonance point of the Grenade, so i better should lower the FG frequency
from 5 to 1.2Mhz to see if that casuses some additional interaction, allthough the Grenade circuit (push pull) is not connected / active now.


Itsu   
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 3270
Itsu,

I thought the purpose of turning Q6 on continuously was to allow you to adjust the collector current to around 150ma.

If you are going to experiment with varying the Q6 base current, I suggest replacing R17 with a fixed 2K resistor in series with a 10K pot (R18 is a minor player, leave it at 2.7K).  This will allow you to vary the base current from approximately .9ma to 6.5ma.  Using the typical Hfe of 80, this will allow you to adjust collector current from 56ma to 520ma.  If you want higher collector current, reducing the fixed resistor from 2K to 1K will allow you to adjust between 80ma and 1amp of collector current.

To achieve collector currents much above above 200ma you will need to reduce the value of your 100R load resistor (or increase the 24 volt supply) 

All numbers and values are approximate, both Vbe and Hfe vary significantly with current and temperature (and between devices).  With no emitter degeneration, collector current will vary considerably as Q6's temperature varies.   

Q6 is a BJT, not a FET.  Base bias should be discussed in terms of base current, not base voltage.

It would be nice to know what and how this circuit is supposed to perform.  That being said, making adjustments using the FG and an arbitrary load may not equate to the desired operating parameters when connected to the rest of the circuit.

Again, I thought Vasik said to set the collector current to around 150ma, using the coil as a collector load and with 24V applied.

PW




PW,

Quote
I thought the purpose of turning Q6 on continuously was to allow you to adjust the collector current to around 150ma.


Yes, it was, and because of being able now to turn Q6 on continuously i was able to set it to its present 130mA by changing R17 to 8.2K.

But.... i noticed that after doing so, the power into the Kacher had dropped to almost nothing, even with 24V on the collector.



So the discussion now is if this 130mA is the correct value for the kacher to work properly by increasing the collector voltage to 100 - 150V, or that we should be looking for another M.O. of this kacher by what verpies called "linear amplification".

Linear amplification of the (ringing) signal from the kacher / antenna via its secondary coil bottom wire back to the base of the transistor which needs another setting / ratio of the R17 / R18 bias resistors.


Thats what i am trying to do now by making R17 (R18) variable by the way you also mentioned.


Parallel to that i will use the present (130mA) setup and increase the collector voltage to 100 - 150V to see if that gives the desired effect as mentioned by Vasik:   "radiant effects (DC on metallic surfaces, white sparks)"  / "create shock waves".


Regards Itsu
   
Pages: 1 ... 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 [38] 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 ... 104
« previous next »


 

Home Help Search Login Register
Theme © PopularFX | Based on PFX Ideas! | Scripts from iScript4u 2021-12-05, 05:30:07