First made in 1925, this tube has a green stripe painted on the side of the glass, from the base to the tip. This indicates that the tube is for Low Frequency use. The stripe measures about 3 mm wide and over time, in many cases, the stripe has worn off.
Dimensioni (LxAxP) incl.pins/tip
x 110 x 35 mm / x 4.33 x 1.38 inch
Bibliografia
British Radio Valves - The Vintage Years: 1904-1925 Pages 30 & 115
AR_LF: Fin Stewart
Fin Stewart
Just Qvigstad
AR_LF: Banneitz, TB der drahtl. Teleph. 1927
Anonimo 15 Collezionista
