1) Lee de Forest and Edwin H. Smythe - METHOD OF COMMUNICATING SIGNALS THROUGH SPACE, US Patent No. 716,334 Patented Dec. 16, 1902.
4°, pp. 6, una tavola. Parzialmente sciolto, tracce di ruggine, strappetti, abrasioni, macchie senza danni al testo, copia discreta. Timbro di studio di
Ingegneria industriale, copia per il Prof. Alessandro Artom.
2) Lee de Forest and Edwin H. Smythe - APPARATUS FOR COMMUNICATING SIGNALS THROUGH SPACE, US Patent No. 716,000 Patented Dec. 16,
1902. 4°, pp. 10, 2 tavole. Alone alle ultime 5 pagine, copia discreta. Le illustrazioni sono ripetute.
3) Lee de Forest- WIRELESS SIGNALS, US Patent No. 730,819 Patented June 9, 1903. 4°, pp. 5, una tavola. Minima mancanza all'angolo inferiore dell'
ultima carta, pieghe, buona copia. Timbro di studio di Ingegneria industriale, copia per il Prof. Alessandro Artom.
4) LEE de FOREST in NEW-YORK CITY- ABSTIMMUNGSVORRICHTUNG FÜR DIE DRAHTLOSE TELEGRAPHIE, Patentschrift Nr. 157346, Ausgegeben den
14 Dezember 1904. 4°, 2 pagine ed una tavola. Timbro di studio di Ingegneria industriale, bella copia.
5) Lee de Forest-SPARK-DETERMINIG APPARATUS FOR WIRELESS SIGNALING, US Patent No. 802,850 Patented Oct 24, 1905. 4°, pp. 3, una tavola.
Piccola mancanza all'angolo interno alto lontano dal testo, buona copia. Timbro di studio di Ingegneria industriale.
" Lee de Forest (August 26, 1873 – June 30, 1961) was an American inventor, self-described "Father of Radio", and a pioneer in the development of sound-on-film recording used for motion pictures. He had over 180 patents, but also a tumultuous career—he boasted that he made, then lost, four fortunes. He was also involved in several major patent lawsuits, spent a substantial part of his income on legal bills, and was even tried (and acquitted) for mail fraud. His most famous invention, in 1906, was the three-element "Audion" (triode) vacuum tube, the first practical amplification device. Although De Forest had only a limited understanding of how it worked, it was the foundation of the field of electronics, making possible radio broadcasting, long distance telephone lines, and talking motion pictures, among countless other applications." (https://en.wikipedia.org/wiki/Lee_de_Forest).