Re: Possible designs for a Ultra low noise 1 Hz to 100kHz amplifier for Phase Noise Analyzer?
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Hi Dave,
Paralleling transistors or amplifiers simply increases the current of phase correlated signals by a factor of N and of non-phase correlated signals (Gaussian noise for example) by a factor of square root of N.
Thus, we obtain an improvement of the signal-to-noise ratio of 6 dB for 4 transistors, 12 dB for 16 transistors, and so on.
This solution was widely used in Hi-Fi several decades ago in the glory days of vinyl records, particularly for moving coil type cells.
F1EKU
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