Kapanadze Cousin - DALLY FREE ENERGY

[itsu]

    Itsu:
   The Stalker diagram that you posted, is not the same as the connections on the Pinoytech set up for the TL494 part of the circuit.
  I had previously tried the Stalker way of doing it, also, but it produced the same problem as the previous TopRuslan 7 set up. Which is where Stalkers circuit idea came from, in any case. So... please look at the Pinoy's layout of the TL494 part of the blue PCB circuit that I just posted in my second to last post, but I removed it afterwards due to oversize.  As that is how I have the TL circuit part connected up.
   My resistors are all 1000 ohm even though the red painted strip is almost orange on two of them, they are are also 1k. I'm trying to stick with the schematics. I did previously follow Verpie's advice and had lower value resistors on. Like 460 ohm to ground, and 10 ohm to the fet drivers. But, I changed those to new resistors as in the Stalker diagram that you just posted.
  Yes, I'm still getting interference of some sort on my scope signals from the gates, not as bad, perhaps. But, it's hard to tell exactly.
  I connected the grounds all together now, as in the STAR formation, to my earth ground line. That helps a little, but not really well enough. The fets are staying cold, so far. But, I have no output at 3t or 168t coils, as yet. Yoke is connected to the fets, and to the 24v power supply. And the grounds are all connected together in the star formation to my earth ground now. Since the cause of the problem may be bad grounding between all the circuits. At least that is what I'm checking on now.

  Sorry TK last nights tests were a dud. No fireworks... 
  Well actually, I did have another filter cap blow in my face like a big firecracker. You would have enjoyed seeing that, maybe.
It was my fault though, as I placed the wrong value cap as a filter cap by accident, somehow. Been having lots of accidents, lately. Working late at night with low lighting levels.

Nick,

i toke that pinoytech PCB layout and created the below (TL494) diagram from it, so that is how i understand you have it connected.

Only difference might be the output resistors R3 - R6  (i have added the C1 decoupling cap myself).

After i  build it on a breadboard, it seems to function well (my floating output levels in yesterdays screenshot were because of a crappy breadboard) even with the 1.5 / 1K output resistors i have nice returns to ground levels now.

The frequency varies from 12Khz to 196KHz,  the duty cycle from 0.3% to 44%, no glitches or oscillations seen.

So if you have problems with this basic TL494 setup (only the TL494 setup), then please try to catch it on video as something must be wrong in your connectons somewhere.

Itsu   

[NickZ]

    Yes, that is the circuit that I'm using. Although you've drawn it a little differently. Thanks for trying it out, and confirming that you were able to get it to run with no signal distortions.. That's good news.
   However I do still have some issues, to iron out.
   Here is a close up view of my TL connections. Pinoy version.

[itsu]

Nick,

i have drawn it the same way as the Stalker diagram for easy comparing.
Yes, your close up view shows what i had drawn.

Make sure this little part work fine, then take the next step by adding the drivers and retest, etc.

As you do not have snubbers installed on your MOSFETs (only the MUR's), and not using the lossless clamp layout, you can expect
nasty spikes etc. when driving the yokes primaries, so start with automotive bulbs as loads like suggested by verpies above.


Itsu

[NickZ]

  Itsu:
  What I have noticed in last nights testing was that the TL494 works fine through out the frequency ranges while the duty cycle is at full duty, or nearly full duty cycle. But still showing at least 4.5v output at pin 9 or 10. If by adjusting one or both controllers the voltage drops below 4.5v, at those pins, the signal messes up. And the best working voltages readings from the 9 and 10 pin is between 5.2v down to 4.5v, but no less than 4.5.  It can't handle getting less than 4.5v to those two pins, 9 and 10, without messing up.
   Any ideas on what to do about that?

   The device is now running on 24v from my PSU, to the yoke and through it's filters and choke coil to the yoke center tap.
   The separate filtered 12v is going to the TL chip, and filtered 15v is going to the UC4420 drivers.
   The Yoke is connected now, to the fets, and is receiving the filtered 24v input to it at the center tap.
   Earth ground is in the STAR formation. 
   Fets are staying stone cold, but no bulbs are lighting on 3t or 28t yoke coil.   
   I still don't know why that's like that. So, I'm looking into it. 

[TinselKoala]

Note how the 494 "outputs" actually work. They are internal transistors, with the Collectors on pins 8 and 11 and the Emitters on pins 9 and 10. The Collectors should be supplied with the operating voltage and when the transistors switch on this voltage is passed to the Emitter pins, which should be connected _directly_ to the input Pins 3 of the 4420s. The 1k pulldowns assure that the 4420 turns off hard when the 494 internal output transistors turn off. What is the reason for the 1.5 k resistors in series with the connections to the 4420s?  I don't think these should be there at all. With 15 volts supplied to the Collectors of the 494 internal output transistors there should be no need for any series resistor between the Emitters (pins 9 and 10) and the 4420 signal input pins 3.