Abstract: | Conclusions A field-effect triode amplifier with series negative current feedback allows a voltage gain of the order of 200–300 to be obtained for a load resistance Rs1 M. The coefficient Ku begins to decrease noticeably only for a feedback resistance above 500 .The current gain reaches (8–10)·103. Increasing the resistances Rs and RL to hundreds of ohms has practically no effect on Ki. For a further increase of Rs and RL the coefficient Ki decreases.The power gain reaches its maximum value (of the order of 104 or more) for Rs100 and RL=10–100 k. An increase in Rs leads to a reduction of Kpmax and to a shift of the extremum of the function Kp=f(RL) into the range of higher values of RL.A large input resistance of the amplifier (tens of megohms and higher) is obtained when Rs increases to 10–100 M. The maximum input resistance is obtained for RL and Rs and may exceed values of from hundreds of megohms to several gigaohms. The minimum input resistance is hundreds of kilohms for RL and Rs0.The minimum input resistance (5–10 k or less) is ensured for Rg and RL0. An increase of the output resistance to hundreds of megohms or higher occurs for Rg and Rs.Translated from Izmeritel'naya Tekhnika, No. 9, pp. 67–70, September, 1971. |