This circuit for dual-gate MOSFET was found in a 90’s Popular Electronics. The coils are according to the frequency range that must be amplified.
We found this circuit in a 1997 documentation. Its purpose is to fan an inverter for fluorescent lamp...
We find this circuit in a 1994 technical documentation. The circuit has a 12 V input and a 33 V...
In the figure we show how two diodes can be used to simulate the center tap of a push-pull driver step....