Show PIECE OF OP QUARTZ CONTROLS RADIO LONDON Oct By 9 9 By The As Associated Press Pross Broadcasting stations can be made to keep ab- ab absolutely absolutely ab absolutely to their allotted wave wave- wavelength wavelength length and avoid Interference with other stations b by means of ot a piece Of quartz no bigger than a post post- post ago ago stamp which Is la on view at atthe atthe the National Radio exhibition at Olympia This at least la U the tho claim ot of the exhibitor who declares that hat a apiece apiece apiece piece ot of o the quartz one ona Inch square and an eighth Of ot an Inch thick placed between plates con con- connected connected connected to grid and filament Of ot a 1 valve will control the wavelength wave Of a mighty broadcasting station |