RF Electronics Chapter 6: Oscillators Page 188
2022, C. J. Kikkert, James Cook University, ISBN 978-0-6486803-9-0.
remains constant, reduces the phase noise further. Other parameters, like the biasing
resistors (Rbc1, Rbc2), the supply voltage and collector current all affect the phase noise
and can be tuned to minimise the phase noise.
Figure 6.24 Low Noise Colpitts oscillator.
If needed compromises can be made to provide more output at the expense of phase noise.
A simple low pass filter can be included at the output to reduce any harmonics. Figure
6.24 shows the resulting circuit. Figure 6.26 shows that the phase noise of 143.2 dB is
13.7 dB lower than that of figure 6.13.
Low Phase Noise Hartley Oscillator
Figure 6.25 Low noise Hartley oscillator.
RF Electronics: Design and Simulation
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