The Transmission and Reception of Ultra-Short Waves That Are Modulated by Several Modulated High Frequencies

In the first part there are mentioned two modulation connections that have been found suitable for modulation with one high frequency or with several high frequencies. It is stated that by careful screening of the parts carrying high frequency, it is possible to prevent direct high-frequency radiation. The question of the pro-component for the permissible degree of balance is discussed from the viewpoints that must be considered in the simultaneous modulation with several high frequencies. Further, there is taken up the disturbances that appear in the receiver due to harmonic vibrations and compound oscillations between the modulated high frequencies. Critical combination oscillations and harmonic vibrations do not appear in the receiving range if this is restricted to one frequency octave. Disturbances due to the direct effect of the high-frequency transmitter through couplings are overcome by adding intermediate circuits. A special connection for modulation with the widest frequency bands is given. In the second part of the paper there is discussed the technique of demodulation connections after a comparison of sensitivity. The screening of all parts carrying high frequency is also very important in receivers in order to avoid additional disturbances. A set for receiving ultra-short waves that are modulated with several high frequencies is described. In conclusion, some possibilities are pointed out for increasing the sensitivity with converter sets.