Give the network determine the input voltage Vs.

7. When the automatic gain control voltage of a radio receiver is measured with a vacuum tube voltmeter whose input resistance is 10 M-ohm, it reads 4.5 V. When an ordinary voltmeter whose input resistance is 10 k-ohm is also connected across the AGC voltage source, both meters read 0.40. What is the internal resistance of the AGC voltage source? 8. A phonograph pick up develops an open-circuit emf of 50 mV and has an internal resistance of 1200 ohm. A. What voltage will it develop across a 4 ohms load resistance? B. What value of load resistance must be used to obtain a 75% eff? C. What is the maximum power output of the pickup? 9. What bleeder resistor is required to complete a voltage divider to give 300 v at 40 mA from a 500 V source of emf if the series dropping resistor is 4 k-ohm.

In an NPN transistor used as an amplifier, which components or connections  control the current flow between the  others?    Pick those that apply.     Either N-doped regions.     The base, symbolized by B controls the current between the emitter, symbolized by E, and the collector, symbolized by C.     The emitter, symbolized by E controls the current between the base, symbolized by B, and the collector, symbolized by C.     The P-doped depletion region.