# input impedance

1. ### Engineering Determine the input impedances of a circuit

1. Homework Statement I'm studying a circuit with BJT's and I'm asked to determine the input resistances of the two amplification steps of the circuit. The circuit I'm analyzing is the following one: 2. Homework Equations 3. The Attempt at a Solution To determine the input resistances I...
2. ### Smith Chart problem

1. Homework Statement An antenna is modeled by a 40ohm resistor in parallel with a capacitor with Xc = -j25. The antenna is fed by a lossless 50ohm signal line 0.15 wavelengths long. Use a Smith Chart to find the input impedance to the transmission line. 2. Homework Equations 3. The...
3. ### Impedance matching a purely resistive load

1. Homework Statement A 25-Ω antenna is connected to a 75-Ω lossless transmission line. Reflections back toward the generator can be eliminated by placing a shunt reactance Z at a distance l from the load (Fig. 1). Determine the values of Z and l. 2. Homework Equations...