This 120V ac power source is built with a simple 120V : 24V center-tapped control transformer and four additional component. This circuit outputs a clean 200-V pk-pk square wave at 60 Hz and can supply up to 20W. The circuit is self-starting and free-running.
If Q1 is faster and has a higher gain than Q2 is [...]

Here is a simple 12 V inverter for application a baby soldering adamant (25W, 35W, etc) in the absence of mains supply. It uses eight transistors and a few resistors and capacitors. Transistors T1 and T2 (each BC547) anatomy an astable multivibrator that produces 50Hz signal. The commutual outputs from the collectors of transistors T1 [...]

This 120V ac power source is built with a simple 120V : 24V center-tapped control transformer and four additional component. This circuit outputs a clean 200-V pk-pk square wave at 60 Hz and can supply up to 20W. The circuit is self-starting and free-running.
If Q1 is faster and has a higher gain than Q2 is [...]