Еуропалық вакуумдық түтікшелердің номенклатурасы және жүйесі

In Europe, the principal method of numbering vacuum tubes ("thermionic valves") was the nomenclature used by the Philips company and its subsidiaries Mullard in the UK, Valvo(de, it) in Germany, Radiotechnique (Miniwatt Dario brand) in France, and Amperex in the United States, from 1934 on. Adhering manufacturers include AEG (de), CdL (1921, French Mazda brand), CIFTE (fr, Mazda Belvu brand), EdiSwan (British Mazda brand), Lorenz (de), MBLE(fr, nl) (be, Adzam brand), RCA (us), RFT(de, sv) (de), Siemens (de), Telefunken (de), Tesla (cz), Toshiba (ja), Tungsram (hu), and Unitra (pl; Dolam, Polam, Telam brands). This system allocated meaningful codes to tubes based on their function and became the starting point for the Pro Electron naming scheme for active devices (including tubes and transistors).

The system allowed for cross referencing with the American RETMA tube designation, the Marconi Osram tube designation, and with military numbering systems such as civilian valve (CV) numbering in the United Kingdom and the Joint Army–Navy (JAN) tube designation in the US. European tube manufacturers agreed on the system, but in the UK, MOV (Marconi Osram Valve), STC/Brimar and Mazda/Ediswan maintained their own systems. Most MOV tubes were cross licensed copies of RCA types, with a British designation. For example, an MOV X63 valve was the same as an RCA 6A8 tube. Brimar, which stood for "British Manufactured American Radio" (valves), used all American designations. STC/Brimar was a UK subsidiary of the American giant ITT (International Telephone and Telegraph). Special quality tubes were sometimes identified by placing the numerical part of the designation between the heater rating and the tube type. The special quality could be anything, from rugged designs for military and industrial use, through devices with exceptionally low noise and microphony, to designs primarily optimised for long life without cathode poisoning when used for switching in a digital computer (but not necessarily with exceptional qualities as an amplifier). For example, an ECC81 manufactured as a special quality (SQ) tube would usually be designated 'E81CC'. The system was not universal as other special quality designation systems existed. An EF91 in its special quality version was designated 'M8083' (the 'M' meant Military) as in this case the standard EF91 was derived from the M8083 military design. Also, the SQ tube was not always designed for the same tasks or given the same Maximum Ratings (for example the E80F was more suitable for audio and electrometer applications, lacking the RF screening of the EF80, with anode and screen grid power ratings roughly half the EF80. Two or more elements in a single envelope were handled by adding letters after the heater identifier, in alphabetical order, so an ECH35 is a 6.3 volt heated triode plus a hexode with an octal base; a PABC80 is a Noval 300mA series heater combination of a single low power diode A, a pair of diodes with common cathode B, and a triode C. There were many ECCnn(n) 6.3V dual triodes. It was the usual practice for power transformers to have a 5 volt insulated winding for rectifier filaments, and a 6.3 volt winding for all the other heaters; virtually all valves with 5V filament are rectifiers with cathode connected to heater, in practice full wave (usable as half wave by strapping both anodes together), e. g. GZ34. For lower voltage lower power requirements, rectifiers with 6.3V heaters and insulated cathodes such as the EZ80 were used, connected to the common filament supply. There is no special nomenclature for EHT rectifiers for cathode ray tubes; the EY51 and EY86 were rated at 17kV with an average current of 350 microamps. The GY501 is another example (31kV at 1.7mA and used the rare B9D base). In practice most "xY" half wave rectifiers are EHT types; but there are plenty of exceptions.

Prior to 1934, Phillips numbers were based on a sequence of one letter to indicate filament current range, followed by one or two digits for the filament voltage, then two digits that gave either the amplification factor (for triodes) or a code beginning with 41 to indicate tetrodes, pentodes and so on.) might be thought to be a germanium Zener diode (although, with only 2 digits for the serial number, it was not really a valid Pro Electron designation). By the time of the introduction of the Pro Electron series most tube names started with either D, E, G, P or U, so confusion between the two systems was unlikely.