6SN7 is a dual triode vacuum tube with an eight-pin octal base. It provides a medium gain (20 dB). The 6SN7 is basically two 6J5 triodes in one envelope.
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6SN7 is a dual triode vacuum tube with an eight-pin octal base. It provides a medium gain (20 dB). The 6SN7 is basically two 6J5 triodes in one envelope.
The 6SN7 was originally released in 1939. It was officially registered in 1941 by RCA and Sylvania as the glass-cased 6SN7GT, originally listed on page 235 of RCA's 1940 RC-14 Receiving Tube Manual, in the Recently Added section, as: 6SN7-GT. Although the 6S-series tubes are often metal-cased, there was never a metal-envelope 6SN7 (there being no pin available to connect the metal shield); there were, however, a few glass-envelope tubes with a metal band, such as the 6SN7A developed during World War II - slightly improved in some respects but the metal band was prone to splitting.[ citation needed ]
Numerous variations on the 6SN7 type have been offered over the years, including:
The American military designator for the 6SN7GA is VT-231. The British called it CV1988. European designations include the 1942 ECC32 (not an exact equivalent), 13D2 and B65.
The 6SN7 has a 6.3 V 600 mA heater/filament. The 12-volt 300 mA filament equivalent is the 12SN7GT or 12SN7GTA. The 14N7 is the Loktal version of the 12SN7GT. There was also a comparatively rare 8V 8SN7 for 450 mA series-string TV sets) and 25 Volt/0.15 Amp heater version: 25SN7GT.
The 1937 6F8G [2] was also an octal-based double triode with essentially the same characteristics as the 6SN7 (or two 6J5's), but in a 'Coke Bottle' large (Outline ST-12) glass envelope with a different pin arrangement and utilising a top cap connection for the first triode's grid (making pin 1 available for a metal shield).
The 6J5, first registered in June 1937, [3] and 6J5GT (registered April 1938; British version L63) were octal single triodes with identical characteristics to one half of a 6SN7. Other equivalents to the 6J5 include:
They in turn were successors to the 1935 RCA 6C5 and 1938 6P5G. [3]
The 1954 6CG7 [4] and 6FQ7 are electrically equivalent to the 6SN7, with nine-pin miniature ("Noval") base (RCA, 1951), also made as an 8.4V 450mA series string heater type as the 8CG7.
In contrast to what some sources claim, the ECC40 with Rimlock base and introduced by Philips in 1948 cannot be considered a successor to the 6SN7 [5] as the electrical characteristics are too different.
The 1946 miniature 12AU7/ECC82, with similar, but not identical, electrical characteristics to the 6SN7 and ECC32, and a filament usable on either 6.3V or 12.6V supplies, is more widely used than the 6CG7/6FQ7.
The 6SN7 was used as an audio amplifier in the 1940-1955 period, usually in the driver stages of power amps. The designer of the famous Williamson amplifier, one of the first true high-fidelity designs, suggested use of the 6SN7 (or B65) in his 1949 revision since it is similar to the original circuit's L63 (=6J5) British single triodes, four of which were used in each channel of his 1947 circuit.
The 6SN7 was one of the most important components of the first programmable electronic digital computer, the ENIAC, which contained several thousand of the tubes. The SAGE computer systems used hundreds of 5692s as flip-flops.
With the advent of television, the 6SN7 was well suited for use as a vertical-deflection amplifier. As screen sizes became larger, voltage and power headroom became insufficient. To address this, uprated versions with higher peak voltage and power ratings were introduced. The GE 6SN7GTA (GE, 1950) had anode dissipation uprated to 5.0 watts. The 1954 GE 6SN7GTB also had controlled heater warmup time, better for series heater strings.
The 6SN7 was considered to be obsolete by the 1960s, replaced by the 12AU7, and became almost unobtainable. With the introduction of semiconductor electronics, vacuum tubes of all types ceased to be manufactured by the major producers. A small demand for vacuum tubes in guitar amplifiers and very expensive high-fidelity equipment remained. As existing stocks ran out, factories in eastern Europe and China started to manufacture the 6SN7, and higher-gain 6SL7. As of 2019 [update] , 6SN7s and 6SL7s are still manufactured in Russia and by JJ Electronic, and are widely available. [6]
A triode is an electronic amplifying vacuum tube consisting of three electrodes inside an evacuated glass envelope: a heated filament or cathode, a grid, and a plate (anode). Developed from Lee De Forest's 1906 Audion, a partial vacuum tube that added a grid electrode to the thermionic diode, the triode was the first practical electronic amplifier and the ancestor of other types of vacuum tubes such as the tetrode and pentode. Its invention founded the electronics age, making possible amplified radio technology and long-distance telephony. Triodes were widely used in consumer electronics devices such as radios and televisions until the 1970s, when transistors replaced them. Today, their main remaining use is in high-power RF amplifiers in radio transmitters and industrial RF heating devices. In recent years there has been a resurgence in demand for low power triodes due to renewed interest in tube-type audio systems by audiophiles who prefer the sound of tube-based electronics.
A vacuum tube, electron tube, valve, or tube, is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied.
12AX7 is a miniature dual-triode 6AV6 vacuum tube with high voltage gain. Developed around 1946 by RCA engineers in Camden, New Jersey, under developmental number A-4522, it was released for public sale under the 12AX7 identifier on September 15, 1947.
Tube sockets are electrical sockets into which vacuum tubes can be plugged, holding them in place and providing terminals, which can be soldered into the circuit, for each of the pins. Sockets are designed to allow tubes to be inserted in only one orientation. They were used in most tube electronic equipment to allow easy removal and replacement. When tube equipment was common, retailers such as drug stores had vacuum tube testers, and sold replacement tubes. Some Nixie tubes were also designed to use sockets.
The term All American Five is a colloquial name for mass-produced, superheterodyne radio receivers that used five vacuum tubes in their design. These radio sets were designed to receive amplitude modulation (AM) broadcasts in the medium wave band, and were manufactured in the United States from the mid-1930s until the early 1960s. By eliminating a power transformer, cost of the units was kept low; the same principle was later applied to television receivers. Variations in the design for lower cost, shortwave bands, better performance or special power supplies existed, although many sets used an identical set of vacuum tubes.
The 6V6 is a beam-power tetrode vacuum tube. The first of this family of tubes to be introduced was the 6V6G by Ken-Rad Tube & Lamp Corporation in late 1936, with the availability by December of both Ken-Rad and Raytheon 6V6G tubes announced. It is still in use in audio applications, especially electric guitar amplifiers.
The EL34 is a thermionic vacuum tube of the power pentode type. The EL34 was introduced in 1955 by Mullard, who were owned by Philips. The EL34 has an octal base and is found mainly in the final output stages of audio amplification circuits; it was also designed to be suitable as a series regulator by virtue of its high permissible voltage between heater and cathode and other parameters. The American RETMA tube designation number for this tube is 6CA7. The USSR analog was 6P27S.
The EL84 is a vacuum tube of the power pentode type. It is used in the power-output-stages of audio-amplifiers, most commonly now in guitar amplifiers, but originally in radios. The EL84 is smaller and more sensitive than the octal 6V6 that was widely used around the world until the 1960s. An interchangeable North American type is the 6BQ5.
The Radio Electronics Television Manufacturers' Association was formed in 1953, as a result of mergers with other trade standards organisations, such as the RMA. It was principally responsible for the standardised nomenclature for American vacuum tubes - however the standard itself had already been in use for a long time before 1953; for example, the 6L6 was introduced in July 1936.
In Europe, the principal method of numbering vacuum tubes 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), RCA (us), RFT(de, sv) (de), Siemens (de), Telefunken (de), Tesla (cz), Toshiba (ja), Tungsram (hu), and Unitra. 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.
12AT7 is a miniature 9-pin medium-gain (60) dual-triode vacuum tube popular in guitar amplifiers. It belongs to a large family of dual triode vacuum tubes which share the same pinout, including in particular the very commonly used low-mu 12AU7 and high-mu 12AX7.
The 12AU7 and its variants are miniature nine-pin medium-gain dual triode vacuum tubes. It belongs to a large family of dual triode vacuum tubes which share the same pinout. 12AU7 is also known in Europe under its Mullard–Philips tube designation ECC82. There are many equivalent tubes with different names, some identical, some designed for ruggedness, long life, or other characteristics; examples are the US military 5814A and the European special-quality ECC82 and E182CC.
The 6N2P,, also sometimes spelled in English "6H2Pi", is a miniature 9-pin dual triode vacuum tube manufactured in USSR, Russia and China with characteristics similar to the 12AX7. The most significant difference between the two is that 6N2P has its two filament elements connected in parallel, unlike the series filament connection of the 12AX7, and it is thus only possible to operate it from a 6.3 volt, 340 mA filament supply
Vacuum tubes produced in the former Soviet Union and in present-day Russia carry their own unique designations. Some confusion has been created in "translating" these designations, as they use Cyrillic rather than Latin characters.
A valve audio amplifier (UK) or vacuum tube audio amplifier (US) is a valve amplifier used for sound reinforcement, sound recording and reproduction.
A double diode triode is a type of electronic vacuum tube once widely used in radio receivers. The tube has a triode for amplification, along with two diodes, one typically for use as a detector and the other as a rectifier for automatic gain control, in one envelope. In practice the two diodes usually share a common cathode. Multiple tube sections in one envelope minimized the number of tubes required in a radio or other apparatus.
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