Back خماسي المساري Arabic Pentod Azerbaijani Пентод Byelorussian Пентод Bulgarian Pentoda BS Pèntode Catalan Pentoda Czech Pentode Danish Pentode German Pentodo Spanish
Electrodes, listed from top to bottom:
anode,
suppressor grid,
screen grid,
control grid,
cathode
A pentode is an electronic device having five electrodes. The term most commonly applies to a three-grid amplifying vacuum tube or thermionic valve that was invented by Gilles Holst and Bernhard D.H. Tellegen in 1926.[1] The pentode (called a triple-grid amplifier in some literature[2]) was developed from the screen-grid tube or shield-grid tube (a type of tetrode tube) by the addition of a grid between the screen grid and the plate. The screen-grid tube was limited in performance as an amplifier due to secondary emission of electrons from the plate.[3] The additional grid is called the suppressor grid. The suppressor grid is usually operated at or near the potential of the cathode and prevents secondary emission electrons from the plate from reaching the screen grid.[4][5] The addition of the suppressor grid permits much greater output signal amplitude to be obtained from the plate of the pentode in amplifier operation than from the plate of the screen-grid tube at the same plate supply voltage. Pentodes were widely manufactured and used in electronic equipment until the 1960s to 1970s, during which time transistors replaced tubes in new designs. During the first quarter of the 21st century, a few pentode tubes have been in production for high power radio frequency applications, musical instrument amplifiers (especially guitars), home audio and niche markets.
- ^ G. Holst and B.D.H. Tellegen, "Means for amplifying electrical oscillations", US Patent 1945040, January 1934.
- ^ "RCA Receiving Tube Manual, 1940"; p118
- ^ Solymar, Lazlo (2012). Modern Physical Electronics. Springer Science and Business Media. p. 8. ISBN 978-9401165075.
- ^ ETC Carney, Allen F. (1998). The Navy Electricity and Electronics Training Series, Module 06: Introduction to Electronic Emission, Tubes, and Power Supplies. Pensacola FL: Naval Education and Training Professional Development and Technology Center. p. 1-47.
- ^ Whitaker, Jerry (2016). Power Vacuum Tubes Handbook, 3rd Edition. CRC Press. p. 87. ISBN 978-1439850657.