1、I - . . _-y- EIA 277 49 - 323qbOO 00b37b0 9 = (Reaffirmed FEBRUAR- January 1963) EIA STANDARD DEfSIGNATION SYSTEM FOR METAL ELECTRON TUBE SHELLS ELECTRONIC INDUSTRTES ASSOCIATION (formerly ET-112) STANDARD RS-277 Formulated by JEDEC Elecfron Tube Council NOTICE These standards, adopted and issued by
2、 the Electronic Industries Association, were formulated by the Electron Tube Council of the Joint Electron Device Engineering Councils. EIA engineering standards are designed to serve the public interest through eliminating mis- understandings between manufacturers and purchasers, facilitating inter
3、changeability and improve- ment of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence of such standards shall not in any respect preclude any member or non-member of EIA from manufacturing or selling products not
4、conforming to such standards. Recommended standards adopted by EIA are without any regard to whether or not their adop- tion may in any way involve patents on articles, materials, or processes. By such action, EIA does not assume any liability to any patent owner, nor does it assume any obligation w
5、hatever ta parties adopting the recommended standards. Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 11 West 42nd Street, New York 36, N. Y. Q Electronic Industries Association i968 All rights reserved Price $.25 Printed in U.S.A. DESIGNATIBN SYSTEM FOR METAL ELECTRON TUBE SH
6、ELLS It shall be standard to indicate the types of metal electron tube shells with designations con- sisting of four parts as follows: 1-The letter M which will identify the bulb as belonging to the metal bulb group. &One or more letters indicating the shape or type of bulb. Note: Wherever possible
7、metal bulb types will be assigned the same designation letter as used in glass bulb manufacture, Le., T-Tubular, S-Straight side, ST-Straight side- Tubular combination, TT-Two Tubular combinations of different diameter, etc. 3-One or more digits indicating maximum diameter of the bulb body in eighth
8、s of an inch or fractions thereof. 4-One or more letters to distinguish bulbs of the same diameter and type but differing in other features such as overall length of dome design, etc. Example Bulb Designation MT8A 1 M indicates the bulb is Metal. 2 T indicates the bulb shape is Tubular. . 3 8 specifies the bulb body is l/ (8/8”) in MAXIMUM DIAMETER. 4 A identifies the bulb as a specific type differing from other bulbs in other major features.
