Figure 6.23 Cascode Amplifier sometimes found in Ham Radio Projects. Plus 12 volts is at the top and ground is at the bottom. At the bottom left is an air wound transformer, most likely one of the windings is resonated. The primary is not shown connected. The top of the secondary is connected to the gate of an N channel F E T, Q1. The bottom of the secondary goes to ground through a 0.01 u f capacitor. The bottom may also be connected to the AGC line or to ground. If ground the capacitor is superfluous. The source of the F E T goes to ground through the parallel combination of a resistor and 0.01 u f capacitor. The drain goes to one end of an inductor. The other end of the inductor goes to the source of Q2. Q2 is directly above Q1 in the diagram. The gate of Q2 goes to ground through a 0.01 u f capacitor. The gate also goes to the junction of two 100 k ohm resistors. The other end of one of the resistors goes to ground and the other one goes to plus 12 volts. Plus 12 volts is bypassed to ground by a 0.01 u f capacitor. The drain of Q2 goes to the bottom of the primary of another air wound transformer. The top of the primary goes to plus 12 volts. The secondary is not shown connected. End verbal description.
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