I'm referring to this video which I saw on youtube. I'm not sure the effectiveness. video 1
In this video, it shows that by increasing the zener diode value from 6.2V to 11.8V (by connecting 6.2V and 5.6V zener diode in series in the video,) the adaptor output will change from 5V to 12V.
I believe that the circuit is based on a ringing choke converter for normal adaptor and that the zener diode (6.2V) is basically used to regulate the auxilliary winding's voltage in order to drive the transistor with constant current source. I found a reference circuit and its operation for similar adaptor in this link. ringing choke converter example
Add information as below:
- Is it true that increasing the zener voltage at the auxilliary winding can increase the output? If yes/no, then why?
- What make me so curious with this video is, from my understanding, basically the secondary output will based on the transformer turns. Is there any part/information that I am missing?