Kapanadze Cousin - DALLY FREE ENERGY

[verpies]

Makes me wonder what other errors that schematic may have, also.

Don't think about them as errors - just another way to do things.

I am using 3 watt 460 ohm resistors in the 9 and 10 pins, looks like some other diagrams are showing 10 ohm resistors, instead. And I am also using 1k to ground, after the 460 ohm resistors.

So you can move these 460Ω resistors in place of the 1K resistors to ground and connect pins 9 & 10 of the TL494 directly to the TC44220s. 
These resistors to ground can go as low as 48Ω but it is very important that these resistors are not wirewound or inductive in any way.

Whoever was designing this circuit was trying to unnecessarily make a protective voltage divider for the TC4420 inputs without realizing that these inputs can easily tolerate any input voltage between -5V and V_DD ...and more.

The DC CHARACTERISTICS Table of the TC4220 clearly states:
"Input Voltage Range     V_IN  –5   —  V_DD+0.3    V"

The resistors to ground are needed as pull-downs by the transistors inside the TL494 acting as emitter followers. 
These transistors can handle 250mA and with a 12V supply the 460Ω resistors to ground will allow only 26mA to flow, so there is no problem with making them 460Ω ...hell, they could even go as low as 48Ω and the TL494 could handle them.

[AlienGrey]

 Is this the way to go ?

https://www.youtube.com/watch?v=ZyfXvFicp8M

[Ed morbus]

Is this real

[AlienGrey]

Is this real

to be honest i don't think those two mess about with BS!

Did you notice the type of EHT TX they were using 'no embedded EHT rect.
but i haven't tried it my self but i have seen florescent tubes planted end on under pillons in a field and they were lit up, it was quite amusing i can tell you that, but i wouldn't want to live under them my self.

If your interested i suggest you try it but please make another tread

[NickZ]

Nick,

I've never had a problem using pin4 DTC for duty control. Try linking out the 12K resistor. You should get up to 45% with a fairly linear response between 0V and around 3.35V with 20% duty at the middle of the voltage range. There is a better way of doing it as Verpies suggests but to avoid messy changes to your board, I suggest you try and get the pin 4 duty control working properly.

   That did the trick alright, and now the duty cycle controller does work, by removing the 12k resistor. To a degree.
A 10k pot would possibly work even better, like apecore is using.
   I will also change the 1000 ohm resistor to something like a 100 ohm, to ground, and run the TLs output direct to the fet drivers,  as Verpies suggested,  tomorrow.