Kapanadze Cousin - DALLY FREE ENERGY

[itsu]

Nick,

i agree with TK about the frequency; 16.6Khz, looking good.

Concerning the drain turnoff signal being rounded off, thats exactly the same is i showed in my latest video to you (linked here:  https://www.youtube.com/watch?v=BDehKNbtoEA&t=364s )
where at time 5.33 i show my both MOSFETs drain / gate signals, see screenshot 1 below.
Yellow and Blue  are gate/drain from MOSFET 1,
purple and green are gate/drain from MOSFET 2.

This rounded off does NOT go away by:

# adding drain to source pull-down resistors (1K, 10K, 56K)
# lowering the pull-down resistor at the TL494 outputs to 100 Ohm (68 Ohm is the minimum according to the data sheet)
# lowering the link resistor between TL494 output and MOSFET driver input to 10 Ohm
# adding a parallel schottky diode across the resistor between MOSFET driver output and gate (anode to gate)

It does go away by using instead of the 10K drain load resistors some 12V automotive bulbs, but it introduces already some spikes, see screenshot 2
again:
Yellow and Blue  are gate/drain from MOSFET 1,
purple and green are gate/drain from MOSFET 2.

Concerning the dead time, like TK mentioned, try to put on both drains or both gates to compare, 44% seems reasonable to me.

How about the MOSFETs, are they getting hot now still?

Regards Itsu

[NickZ]

OK, sounds like things are working fine, so far.
Using calctool gives me 16.667KHz. So, that also compares with your frequency calculations. Great. So I am in the needed frequency ranges. Next will.be to connect the TL/UC drivers to the rest of the yoke/grenade system,  and check for MOSFET overheating. If the FETs stay cool, I'll connect the Kacher up also. Then see about matching their frequencies.
  I'll post some more scope shots after I connect up the rest of the yoke and grenade circuits.
  Thanks a lot for your help guys. I wish that you were both working on this project, as well, so that we could compare the results.

[itsu]

Nick,

be aware that without any snubbers on the drains, you very probably will see some nasty spikes when probing your drains.
At 24V input, those spikes could easily peak to over 200V which is your MOSFETs max drain voltage and could in the long run cause damage to your MOSFETs even without them getting hot.

Use short runs and monitor the drains.   When over 200V peaks are detected, you need to start thinking of using snubbers to divert those peaks or use the lossless clamp design.


Itsu

[MonsieurX]

After reading you, I will start something.
As I see you work on mounts with TL494, I like it.
I have seen that are differents model, what kind of TL494 may i use ?.
Can you tell me the 2 diagrams to realize, because there are many assemblies and I do not have your experience to avoid such a montage that works badly.
My oscilloscope is a HAMEG 303-6 2 X 35 Mhz. Digital multimeter and frequency meter.
If you live in Europe, where do you order your components?
Here we have CONRAD, but a little expensive.
Questions: I see a Nanoseconde generator, but a TL494 can not work at 1 Ghz, despite my reads I do not understand. If you can enlighten me.
I have not Yok from old TV.
Thank you.

[NickZ]

   X:
   The TL494 circuit is only for the push pull generator. It needs to work from 10KHz to 30KHz, or so.
Kacher circuit is for the high frequency impulses,