Valve Electroni...

Thermionic emission from a heated filament varies with its temperature T as

Due to S.C.R in vacuum tube

In a triode, gm = 2×10⁻³ohm⁻¹,μ = 42, resistance load, R = 50 kilo ohm. The voltage amplification obtained from this triode will be

In an amplifier the load resistance R_L​ is equal to the plate resistance (r_β​). The voltage amplification is equal to

If R_p​ = 7kω , gm ​= 2.5 millimho , then on increasing plate voltage by 50V, how much the grid voltage is changed so that plate current remains the same?

In a triode amplifier, μ = 25,r_p ​ =40 kilo ohm and load resistance R_L​=10 kilo ohm. If the input signal voltage is 0.5 volt, when output signal voltage will be

The amplification factor of a triode is 20. If the grid potential is reduced by 0.2 volt  then keep the plate current constant its plate voltage is to be increased by

For a triode r_p​ = 10 kilo ohm and gm​ = 3 milli mho If the loads resistance is double of plate resistance, then the value of voltage gain will be

In an experiment, the saturation in the plate current in a diode is observed at 240 V. But a student still wants to increase the plate current. It can done, if

For a given triode μ=20. The load resistance is 1.5 times the anode resistance. The maximum gain will be