JFET-Bipolar Cascode Circuit
This is JFET-bipolar cascode circuit. It will provide full video output for the CRT cathode drive. The gain of this circuit is about 90. Here is the circuit :
This circuit employs 2N4091 JFET to solve Miller capacitance problems using cascode configuration. It will alow direct drive from the video detector. The video amplifier will not amplify the 45MHz sound frequency because of variable inductor and an m derived filter using stray capacitance. [Source: National Semiconductor Application Note]