When using a device beyond it's ratings, or when using it for a purpose different from the intended application, the performance may not coincide with that performance claimed in the specifications. This certainly applies to the simulation results shown in post #19. What IS the point being made, anyway??

 

I showed that the input RMS voltage should not be 12 V. It turned out to be 18V RMS. The number of turns of the windings is equal to the voltage multiplied by 5. Therefore, with an input voltage of 230V RMS on the secondary winding you get 18V RMS. This was required because of the strong ripple at a load current of 1A. It is necessary to increase the capacitance of the filtering capacitor. I also showed that I needed a heat sink because of the high power dissipation of the IC. I also added an additional resistor to maximize the voltage to 12V.
I also showed the average output voltage, ripple voltage and the power dissipated by the chip depending on the position of the resistor slider.
So I decided to give a simulation lesson in LTspice.

 

I showed that the input RMS voltage should not be 12 V. It turned out to be 18V RMS. The number of turns of the windings is equal to the voltage multiplied by 5. Therefore, with an input voltage of 230V RMS on the secondary winding you get 18V RMS. This was required because of the strong ripple at a load current of 1A. It is necessary to increase the capacitance of the filtering capacitor. I also showed that I needed a heat sink because of the high power dissipation of the IC. I also added an additional resistor to maximize the voltage to 12V.
I also showed the average output voltage, ripple voltage and the power dissipated by the chip depending on the position of the resistor slider.
So I decided to give a simulation lesson in LTspice.

Hi,

Oh ok very good. Nice presentation too.

And yes, we did not yet look at the power dissipation nor the input voltage requirement in detail considering the ripple. It's good that you showed that also.