WFC VIC

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Also, the VIC wil only output spikes, because the input is a blockpulse, induced emf = - dPhi/dt (edit minus actually), thus a spike will occur on the rising and falling edge, during high state, the output of the VIC is low.
Some VIC illustrations show a blockpulse on the input, which induces spikes.
Others show pulses with a rounded top, which induces the same signal on the output.
Please correct me if i'm wrong, it's been a while.

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The very short impulses you see when switching in transformers occurs, is usually due to the stray inductances. These are the more extreme, the steeper your dv/dt is. E.g. they occur most badly on rectangular waveforms. Usually you use small snubber circuits to get rid of them, so that they are not able to destroy your parts.

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I also thought this recently but is not alan, The transformer must not work in the kick back mode but normal transformer mode. I think.


Meyer gave us calculations for common transformers and not even one kickback calculation. this reinforce what i feel now. 

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Actually the scope shot is up side down. The reason for this is because of what you are referencing the signal to. I've tested this with my scope and I've had the same thing happen, where my image would be opposite to what it actually is. if you look at the image below you'll see that this is correct.
(http://www.globalkast.com/images/stanmeyer/8XA_Scope_Shot_from_Don.PNG)

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@Tony: Just a little addition. The scope shot you show is wrong in one relation, because you didn't turn the shot upside down, but turned it 180° so the time on your shot is backwards running! Just to mention the difference to my corrected scope shot.
@sebosfato: BTW. What kind of pulsing circuitry are you using. The NE555 Stuff? I would recommend you do it like I did, e.g. I just took a small Microcontroller plugged some VFD to it and soldered a small joystick on it. Finished. Very easy to adjust and to build, and the best part is, the uC already has a comparator on it for easy pickup-coil sensing and self-adjusting. Maybe you can do something similar for yourself.
BTW, when we are just talking about this: When you look at the patent circuit, you see how he designed the circuit, and from this you can definitely say, it is not in a flyback configuration.


Edit: Here's a pic of my driver (on the right side is the coil driver circuit): (as you can see, I'm not a friend of nice packaging )
(http://img543.imageshack.us/img543/1231/driverp.jpg)

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Cool, what microcontroller ar you using and how do you vary the values? Potmeters or via telnet?

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@Tony: Just a little addition. The scope shot you show is wrong in one relation, because you didn't turn the shot upside down, but turned it 180° so the time on your shot is backwards running! Just to mention the difference to my corrected scope shot.
@sebosfato: BTW. What kind of pulsing circuitry are you using. The NE555 Stuff? I would recommend you do it like I did, e.g. I just took a small Microcontroller plugged some VFD to it and soldered a small joystick on it. Finished. Very easy to adjust and to build, and the best part is, the uC already has a comparator on it for easy pickup-coil sensing and self-adjusting. Maybe you can do something similar for yourself.
BTW, when we are just talking about this: When you look at the patent circuit, you see how he designed the circuit, and from this you can definitely say, it is not in a flyback configuration.


Edit: Here's a pic of my driver (on the right side is the coil driver circuit): (as you can see, I'm not a friend of nice packaging )
(http://img543.imageshack.us/img543/1231/driverp.jpg)

Nice uC and driver you have Kali_ma_Amar!
I'm using a STM32 (cortex-m3) uC for PULSE and GATE signal generation. For the feedback and scanner I'm using also Stan his PLL circuit.

I'm very interested if you would share your schematics of your boards.
I'm using a MOSFET driver but want it to swap it to transistor.

br,
Webmug

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I just realized, that I shouldn't have posted this pic in here. It now gets way too offtopic. Sorry for that.
Just in short. To answer the questions, so that discussions about the VIC can continue.
For big projects I also use the cortex chips (LPCs). But this application needs no CPU power, but a good interface chip (which can drive I/Os). For these I always take the AVRs.  To interact with the menu (change values, select mode, etc.), there's an analog joystick soldered on the board.
@Webmug: Why do you wanna change to a transistor design? This application is THE application for FETs (hard switching on and off). Doesn't make absolutely no sense to me, to use transistors. Surely in Stans time, good PowerFETs were not yet available. I just used a good PowerFET together with the usual circuitry (IXDD414 for driving, Z-Diode at the gate and Transil-Diode over the FET, and surely the diode in series with the FET (as in Stans circuit) not to limit resonance). If you work with a low 12V voltage like Stan, then IMHO a transistor would just be a waste of additional energy compared to a good FET. Unfortunately the series-diode is also a big waste but I wouldn't know how to do it otherwise.

For the feedback and scanner I'm using also Stan his PLL circuit.

Why that? If you have a uC, the uC can easily do the PLL stuff. The frequencies used here are so low , that a uC has surely no problems with that. And you can lock-in much faster in SW. For higher frequencies (>50-100KHz) like used in the SSTCs, the usual PLL circuit, as Stan used is needed, but at <50KHz I would surely just do it in SW.

Back to the VIC. On saturday I replicated the 8xA circuit (I finally found my SCRs ). But the results I got puzzle me even more...I really think understanding the functioning of the 8xA circuit, what the coils really exactly do here and how they interact with the SCR and the pulsing, is one major key in understanding the whole VIC.