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SynopsisA large-signal analysis of varactor harmonic generators without idlers is given. The voltage across the varactor is expressed as a Fourier series in the harmonic charges, and, by expressing the input circuit as an impedance, and the output circuit as a voltage generator in series with an impedance, the relevant coefficients of the series are found. It is found expedient to express the circuit in this way in order to determine the coefficients without any approximation. The efficiency is then calculated as a function of input power; it is found that, for maximum efficiency, input and output resistances should be equal and an expression is given to determine their value. Finally, design curves are given for second-, third-and fourth-harmonic generators, from which optimum operating conditions can be found.List of principal symbols capacitance of varactor capacitance of varactor at reverse breakdown voltage capacitance of varactor at zero voltage generator e.m.f. cutoff frequency at V R current through varactor at input frequency current through varactor at output frequency amplitude of 1\ amplitude of I N tuning inductance in input circuit tuning inductance in output circuit index, dependent on junction doping order of multiplication = normalised amplitude of Q x = normalised amplitude of Q N = charge on varactor -charge on varactor at reverse breakdown voltage = component of Q at fundamental frequency = component of Q at output frequency = fundamental-frequency Q factor of biased varactor = amplitude of (21 = amplitude of Q± = load resistance = generator series resistance = normalised R g = normalised R L -varactor series resistance = voltage across varactor = bias voltage diffusion voltage reverse breakdown voltage of diode V-V R

In cities the world over, we are able to determine stability in daily existence, to identify with our social spaces, because modes of transport have become essential components of subjective autonomy. But would it not be just as accurate to say that in transit, modern life puts the self in abeyance? The author argues that the ways we allow ourselves to be moved around in "traffic space" create a passivity that renders almost invisible the complex mechanics of movement, which we become alert to only at the moment of breakdown, precisely when they become a threat to autonomy. Our trafficking has an almost narcotic effect, rendering us immobile against the continual movements that constitute urban life, one that also magnifies out of all proportion the accidents or aberrations that sometimes disturb our traffic space, making it seem as if we may easily descend into an uncontrollable chaos.