Audiofrequency Measurement of Jfet Noise Vs . Temperature in a High Impedance Preamplifier
نویسندگان
چکیده
We describe a high impedance audiofrequency preamplifier and present au-diofrequency noise spectra for 2N4416 and U311 JF'ET's, in a temperature range from room temperature to 80O.K. It is found that optimum noise performance is obtained at-140'K. We present an analysis of some of the sources of noise. Amplifier input capacitance is a.lso measured and discussed.
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