ETI - An Overview
Subminiature CV4501 tube (SQ Variation of EF72), 35 mm lengthy × ten mm diameter (excluding leads) Early tubes used a metallic or glass envelope atop an insulating bakelite base. In 1938 a method was created to utilize an all-glass development[51] with the pins fused in the glass base of your envelope. This allowed the look of a A lot lesser tube