Improvements in or relating to crystal apparatus for use in connection with electric oscillations
264,270. Wilcockson, J., and Roberts, H. W. Oct. 31, 1925. Crystal detectors; non-therniionic amplifiers; oscillation generators.-A crystal combination of alum in contact with saltpetre is stated to rectify and amplify received wireless signals. Under the influence of radio-frequency oscillations, the com. bination also emits a ray capable of oxidizing metals and influencing an adjacent electroscope. As shown in Fig. 1, the alum 3 and saltpetre 5 are mounted in insulating blocks 4, 6, carried by two casings 7, 8 which may telescope together to maintain contact between the crystals; or suitable means may be provided to feed the crystals towards each other automatically. An electric potential of the value normally used across the plate and filament of a thermionic valve is applied to the alum 3 by conductors 9, 10 taken to suitable terminals 9A, 10<A> on a plug base as shown, whilst a lower potential corresponding to the filament voltage is applied to the saltpetre through conductors 11, 12 from the terminals 11<A>, 12<A>. Fig. 3 shows the circuit arrangement of the crystal combination as used for receiving wireless signals.