“The Theory and Characteristics of Radiotrons” Parts I and II Part I from General Electric Review, Vol. 30, No. 8, August, 1927, pp. 400-407 Part II from General Electric Review, Vol. 30, No. 9, September, 1927, pp. 453-464 Scanned by John T. M. Lyles, K5PRO, August, 2007