543:
391:
demonstrating that, contrary to what Edison and others had long asserted, incandescent lamps could function more efficiently and with longer life if the glass envelope was filled with low-pressure inert gas rather than a complete vacuum. However, this only worked if the gas used was meticulously 'scrubbed" of all traces of oxygen and water vapor. He then applied the same approach to producing a rectifier for the newly developed "Coolidge" X-ray tubes. Again contrary to what had been widely believed to be possible, by virtue of meticulous cleanliness and attention to detail, he was able to produce versions of the
Fleming Diode that could rectify hundreds of thousands of volts. His rectifiers were called "Kenotrons" from the Greek
523:
567:
462:". They were very unreliable, requiring frequent adjustment of the cat's whisker and offered no amplification. Such systems usually required the user to listen to the signal through headphones, sometimes at very low volume, as the only energy available to operate the headphones was that picked up by the antenna. For long distance communication huge antennas were normally required, and enormous amounts of electrical power had to be fed into the transmitter.
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52:(which was also the cathode) was at the lower left inside the tube, but has burned out and is no longer present. The filament's connecting and supporting wires are visible. The plate is at the middle top, and the grid is the serpentine electrode below it. The plate and grid connections leave the tube at the right.
179:; a new type of detector would allow de Forest to market his own system. He eventually discovered that connecting the antenna circuit to a third electrode placed directly in the space current path greatly improved the sensitivity; in his earliest versions, this was simply a piece of wire bent into the shape of a
465:
The Audion was a considerable improvement on this, but the original devices could not provide any subsequent amplification to what was produced in the signal detection process. The later vacuum triodes allowed the signal to be amplified to any desired level, typically by feeding the amplified output
327:
The problem was that (possibly to distance his invention from the
Fleming valve) de Forest's original patents specified that low-pressure gas inside the Audion was essential to its operation (Audion being a contraction of "Audio-Ion"), and in fact early Audions had severe reliability problems due to
409:
He soon realized that his "vacuum" Audion had markedly different characteristics from the de Forest version, and was really a quite different device, capable of linear amplification and at much higher frequencies. To distinguish his device from the Audion he named it the "Pliotron", from the Greek
286:
various types of radio transmitting and receiving apparatus, (examples of which are illustrated on this page). However, although he routinely described these devices as using "Audions", they actually used high-vacuum triodes, using circuitry very similar to that developed by other experimenters.
172:
terminal of a 22–volt battery via a pair of headphones, the negative terminal being connected to one side of the lamp filament. When wireless signals were applied to the wire wrapped around the outside of the glass, they caused disturbances in the current which produced sounds in the headphones.
285:
He always referred to the vacuum triodes developed by other researchers as "Oscillaudions", although there is no evidence that he had any significant input to their development. It is true that after the invention of the true vacuum triode in 1913 (see below), de Forest continued to manufacture
208:
had been the bane of the telephone industry for at least two decades. (Ironically, in the years of patent disputes leading up to World War I, it was only this "loophole" that allowed vacuum triodes to be manufactured at all since de Forest's grid Audion patent did not mention this application).
171:
heated by a conventional lamp filament behaved much the same way, and that if a wire were wrapped around the glass housing, the device could serve as a detector of radio signals. In his original design, a small metal plate was sealed into the lamp housing, and this was connected to the positive
421:
Essentially, he referred to all his vacuum tube designs as
Kenotrons, the Pliotron basically being a specialized type of Kenotron. However, because Pliotron and Kenotron were registered trademarks, technical writers tended to use the more generic term "vacuum tube". By the mid-1920s, the term
390:
Langmuir had long suspected that certain assumed limitations on the performance of various low-pressure and vacuum electrical devices, might not be fundamental physical limitations at all, but simply due to contamination and impurities in the manufacturing process. His first success was in
1279:
This appears in some Audion Bulbs and not in others. If allowed to persist, the vacuum automatically increases. For this reason the glow should not be allowed to appear and certainly not to continue, as the vacuum may rise to a very high value, requiring very high voltage in the “B”
1267:
Regular Audion
Detector Bulbs are not adapted for the reception of continuous waves, because the vacuum is not correct for the purpose and because the filaments must be operated at such a high intensity that they give very short service, making them unnecessarily
466:
of one triode into the grid of the next, eventually providing more than enough power to drive a full-sized speaker. Apart from this, they were able to amplify the incoming radio signals prior to the detection process, making it work much more efficiently.
405:
However he took a somewhat unorthodox approach. Instead of trying to stabilize the partial vacuum, he wondered if it was possible to make the Audion function with the total vacuum of a
Kenotron, since that was somewhat easier to stabilize.
331:
As well as de Forest himself, numerous researchers had tried to find ways to improve the reliability of the device by stabilizing the partial vacuum. Much of the research that led to the development of true vacuum tubes was carried out by
199:
De Forest and everybody else at the time greatly underestimated the potential of his grid Audion, imagining it to be limited to mostly military applications. It is significant that de Forest apparently did not see its potential as a
422:"Kenotron" had come to exclusively refer to vacuum tube rectifiers, while the term "Pliotron" had fallen into disuse. Ironically, in popular usage, the sound-alike brands "Radiotron" and "Ken-Rad" outlasted the original names.
430:
De Forest continued to manufacture and supply
Audions to the US Navy up until the early 1920s, for maintenance of existing equipment, but elsewhere they were regarded as well and truly obsolete by then. It was the vacuum
315:
in New York and Boston, respectively, presenting his paper "Some Recent
Developments in the Audion Receiver", which was published in September. A combination of the two papers was reprinted in other journals such as the
155:. The Audion tubes were mounted upside down to prevent the delicate filaments from sagging and touching the grids. This receiver provided the ability to choose operation of either one of the two provided detector tubes.
190:
The Audion provided power gain; with other detectors, all of the power to operate the headphones had to come from the antenna circuit itself. Consequently, weak transmitters could be heard at greater distances.
522:
135:. The many practical applications for amplification motivated its rapid development, and the original Audion was superseded within a few years by improved versions with a higher vacuum.
402:
He then turned his attention to the Audion tube, again suspecting that its notoriously unpredictable behaviour might be tamed with more care in the manufacturing process.
566:
1309:
1234:, Lee de Forest, Scientific American Supplement No. 1665, November 30, 1907, pages 348-350, Scientific American Supplement No. 1666, December 7, 1907, page 354–356.
511:
in 1959, although vacuum tubes remain to this day in such applications as high-powered transmitters, guitar amplifiers and some high fidelity audio equipment.
2359:
282:), and de Forest became embroiled in many radio-related patent disputes. De Forest was famous for saying that he "didn't know why it worked, it just did".
242:
Later design of an audion tube. The grid and plate are in two parts on either side of the central filament. In both these tubes the filament is burned out.
384:
French triodes. The French government gained the right to manufacture
Audions in 1912 when de Forest failed to renew his French patents for lack of $ 125.
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2183:
1824:
1161:
127:, it found little use until its amplifying ability was recognized around 1912 by several researchers, who used it to build the first amplifying
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2642:
328:
this gas being adsorbed by the metal electrodes. The
Audions sometimes worked extremely well; at other times they would barely work at all.
1741:
1522:
1302:
756:
Non-paywalled reprint of the DeForest presentation at the
October 26, 1906 New York meeting of the AIEE. Text version available at the
913:
735:
204:
at the time he filed the patent claiming it, even though he had previously patented amplification devices and crude electromechanical
1505:
1401:
1118:
783:
711:
625:
De Forest patented a number of variations of his detector tubes starting in 1906. The patent that most clearly covers the Audion is
473:. The combination of much more efficient transmitters and much more sensitive receivers revolutionized radio communication during
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and gave the Audion non-linear characteristics and erratic performance. Originally developed as a radio receiver
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1951:
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1162:
http://www.britannica.com/EBchecked/topic/1262240/radio-technology/25131/The-Fleming-diode-and-De-Forest-Audion
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1962:
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31:
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The Audion Amplifier Bulb is entirely different from the Audion Detector Bulb in construction and vacuum.
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to document the electrical principles of the Audion. Armstrong published his explanation of the Audion in
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1973:
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patent, Armstrong was able to demonstrate conclusively that de Forest still had no idea how it worked.
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163:, and early wireless experimenters had noticed that this conductivity was affected by the presence of
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This was a significant development as existing commercial wireless systems were heavily protected by
905:
Dawn of the Electronic Age: Electrical Technologies in the Shaping of the Modern World, 1914 to 1945
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1994:
1902:
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in 1912 made inexpensive sound radio transmission possible, and was responsible for the advent of
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1906 photograph of the original Audion tube, from New York Public Library Digital Gallery
238:
The first prototype Audion with the grid (zigzag wires) between the filament and plate.
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108:. A low power signal at the grid could control much more power in the plate circuit.
65:
1209:"The Pure Electron Discharge and Its Applications in Radio Telegraphy and Telephony"
1198:
1172:"The Pure Electron Discharge and Its Applications in Radio Telegraphy and Telephony"
845:
Planar Microwave Engineering: A Practical Guide to Theory, Measurement, and Circuits
683:, Nos. 1665 and 1666, November 30, 1907 and December 7, 1907, p.348-350 and 354-356.
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264:). De Forest continued to claim that he developed the Audion independently from
61:
49:
45:
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757:
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Prior to the introduction of the Audion, radio receivers had used a variety of
37:
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320:. When Armstrong and de Forest later faced each other in a dispute over the
159:
It had been known since the middle of the 19th century that gas flames were
105:
81:
552:
transmitters, built by de Forest around 1916. The invention of the Audion
17:
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1979:
1968:
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272:(for which Fleming received Great Britain patent 24850 and the American
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1923:
1908:
1762:
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1367:
662:. American Institute of Electrical and Electronics Engineers: 735–763.
480:
By the late 1920s such "tube radios" began to become a fixture of most
443:
1070:
Radio's Conquest of Space the Experimental Rise in Radio Communication
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258:), and the "triode" (three-electrode) version was patented in 1908 (
454:. The most popular crystal detector consisted of a small piece of
104:
because it was the first widely used electronic device which could
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1984:
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households, and remained so until long after the introduction of
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1291:
1238:
Lee de Forest's Audion Piano on '120 years Of Electronic Music'
1147:"Telephone History - Empire of The Air: The Men Who Made Radio"
1243:
https://books.google.com/books?id=YEASAAAAIAAJ&pg=PA166
248:
De Forest was granted a patent for his early two-electrode
458:
crystal probed by a fine wire commonly referred to as a "
311:
graphs. In March and April 1915, Armstrong spoke to the
115:
than later vacuum tubes; the residual gas limited the
1129:, Chapter V, Steven Johnson, Riverhead Books, (2011).
736:"The Audion - A new receiver for wireless telegraphy"
307:
in December 1914, complete with circuit diagrams and
652:"The Audion; A New Receiver for Wireless Telegraphy"
352:
Audions and early triodes developed from them, 1918
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2009:
1937:
1843:
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1549:
1454:
1336:
1325:
1036:
1034:
1232:The Audion: A new Receiver for Wireless Telegraphy
872:Hempstead, Colin; Worthington, William E. (2005).
637:, filed January 29, 1907, issued February 18, 1908
972:"Some Recent Developments in the Audion Receiver"
937:"Some Recent Developments in the Audion Receiver"
469:Vacuum tubes could also be used to make superior
1110:Wireless: From Marconi's Black-box to the Audion
927:
925:
435:that made practical radio broadcasts a reality.
72:in 1906. Improved, it was patented as the first
875:Encyclopedia of 20th-Century Technology, Vol. 2
378:which bought the rights from de Forest in 1913.
1089:1973 postage stamp honoring de Forest's audion
848:. Cambridge University Press. pp. 13–14.
395:(empty, contains nothing, as in a vacuum) and
27:Electronic detecting or amplifying vacuum tube
2353:
1303:
1096:Radio Corp. v. Radio Engineering Laboratories
679:The link is to a reprint of the paper in the
8:
1103: (United States Supreme Court 1934).
252:version of the Audion on November 13, 1906 (
867:
865:
645:
643:
2360:
2346:
2338:
1333:
1310:
1296:
1288:
897:
895:
706:. Greenwood Publishing Group. p. 28.
318:Annals of the New York Academy of Sciences
60:was an electronic detecting or amplifying
1073:. Taylor & Francis. pp. 178–184.
908:. John Wiley & Sons. pp. 14–15.
693:
691:
689:
594:
592:
590:
64:invented by American electrical engineer
776:Newnes Dictionary of Electronics, 4th Ed
418:, more signal coming out than went in).
167:. De Forest found that gas in a partial
812:. Lehigh University Press. p. 77.
704:Historical Dictionary of American Radio
586:
518:
507:, invented in 1947 and implemented in
414:(more or extra, in this sense meaning
1228:. (Includes comments from de Forest.)
878:. Taylor & Francis. p. 643.
837:
835:
833:
831:
829:
7:
1742:Three-dimensional integrated circuit
1019:(11). Experimenter Publications: 990
100:(the anode). It is important in the
76:in 1908, consisting of an evacuated
1523:Programmable unijunction transistor
358:De Forest Audions and oscillaudions
1424:Multi-gate field-effect transistor
1251:"Practical Pointers on the Audion"
1046:"Operating Features of the Audion"
123:by adding a grid electrode to the
25:
2695:Audiovisual introductions in 1906
1402:Insulated-gate bipolar transistor
1646:Heterostructure barrier varactor
1373:Chemical field-effect transistor
565:
541:
521:
225:
216:
1694:Mixed-signal integrated circuit
1067:McNicol, Donald Monroe (1946).
650:de Forest, Lee (January 1906).
499:has been largely superseded by
1006:"Evolution of the Vacuum Tube"
734:de Forest, Lee (30 Nov 1907).
681:Scientific American Supplement
1:
1245:de Forest and Armstong debate
605:. IOS Press. pp. 17–22.
1725:Silicon controlled rectifier
1587:Organic light-emitting diode
1477:Diffused junction transistor
548:Some of the earliest Audion
340:(GE) research laboratories.
313:Institute of Radio Engineers
202:telephone repeater amplifier
1529:Static induction transistor
1466:Bipolar junction transistor
1418:MOS field-effect transistor
1390:Fin field-effect transistor
1004:de Forest, Lee (May 1930).
698:Godfrey, Donald G. (1998).
668:10.1109/t-aiee.1906.4764762
268:'s earlier research on the
2721:
1736:Static induction thyristor
1249:Cole, A. B. (March 1916).
1225:10.1109/jrproc.1915.216680
1127:Where Good Ideas Come From
953:10.1109/jrproc.1915.216677
902:Nebeker, Frederik (2009).
88:(the cathode, made out of
29:
2483:(Hexode, Heptode, Octode)
1905:(Hexode, Heptode, Octode)
1657:Hybrid integrated circuit
1500:Light-emitting transistor
1191:10.1109/jproc.1997.628726
991:10.1109/jproc.1997.573757
806:Hijiya, James A. (1992).
602:History of Electron Tubes
536:and announced April, 1914
488:radios in the mid-1950s.
2502:Backward-wave oscillator
1952:Backward-wave oscillator
1662:Light emitting capacitor
1518:Point-contact transistor
1488:Junction Gate FET (JFET)
364:Pliotrons, developed at
1963:Crossed-field amplifier
1482:Field-effect transistor
1179:Proceedings of the IEEE
979:Proceedings of the IEEE
842:Lee, Thomas H. (2004).
778:. Newnes. p. 331.
574:Electrical Experimenter
161:electrically conductive
32:Audion (disambiguation)
2376:Theoretical principles
2132:Voltage-regulator tube
1699:MOS integrated circuit
1564:Constant-current diode
1540:Unijunction transistor
1276:BLUE DISCHARGE OF GLOW
1273:Also page 44 stating,
1264:Also page 43 stating,
1213:Proceedings of the IRE
1107:Hong, Sungook (2001),
1090:
941:Proceedings of the IRE
599:Okamura, SĹŤgo (1994).
572:Audion advertisement,
460:cat's-whisker detector
399:(device, instrument).
387:
297:worked with professor
295:Edwin Howard Armstrong
156:
133:electronic oscillators
53:
2532:Inductive output tube
2201:Electrolytic detector
1974:Inductive output tube
1790:Low-dropout regulator
1705:Organic semiconductor
1636:Printed circuit board
1472:Darlington transistor
1319:Electronic components
1088:
1044:(December 12, 1914).
374:triodes developed at
351:
344:Kenotron and Pliotron
299:John Harold Morecroft
146:
102:history of technology
40:
2674:List of tube sockets
2669:List of vacuum tubes
2507:Beam deflection tube
2019:Beam deflection tube
1688:Metal oxide varistor
1581:Light-emitting diode
1435:Thin-film transistor
1396:Floating-gate MOSFET
770:Amos, S. W. (2002).
528:The first Audion AM
503:devices such as the
426:Applications and use
266:John Ambrose Fleming
195:Patents and disputes
30:For other uses, see
2705:American inventions
2592:Traveling-wave tube
2383:Thermionic emission
1995:Traveling-wave tube
1795:Switching regulator
1631:Printed electronics
1608:Step recovery diode
1385:Depletion-load NMOS
1170:(September 1997) ,
1145:Lewis, Tom (1991).
758:Early Radio History
740:Scientific American
628:U.S. patent 879,532
509:integrated circuits
291:Columbia University
279:U.S. patent 803,684
261:U.S. patent 879,532
255:U.S. patent 841,386
2300:Crystal oscillator
2160:Variable capacitor
1835:Switched capacitor
1777:Voltage regulators
1651:Integrated circuit
1535:Tetrode transistor
1513:Pentode transistor
1506:Organic LET (OLET)
1493:Organic FET (OFET)
1207:(September 1915),
1101:293 U.S. 1
1091:
965:. Republished as
935:(September 1915).
558:radio broadcasting
515:Application images
471:radio transmitters
388:
157:
54:
2682:
2681:
2621:Numbering systems
2602:Video camera tube
2587:Talaria projector
2369:Thermionic valves
2335:
2334:
2295:Ceramic resonator
2107:Mercury-arc valve
2059:Video camera tube
2011:Cathode-ray tubes
1771:
1770:
1379:Complementary MOS
530:radio transmitter
452:crystal detectors
111:Audions had more
80:containing three
16:(Redirected from
2712:
2492:Cathode-ray tube
2362:
2355:
2348:
2339:
2189:electrical power
2074:Gas-filled tubes
1958:Cavity magnetron
1785:Linear regulator
1334:
1312:
1305:
1298:
1289:
1261:
1227:
1205:Langmuir, Irving
1201:
1185:(9): 1496–1508,
1176:
1168:Langmuir, Irving
1158:
1157:on May 11, 2014.
1153:. Archived from
1123:
1098:
1075:
1074:
1064:
1058:
1057:
1056:(24): 1149–1152.
1050:Electrical World
1042:Armstrong, E. H.
1038:
1029:
1028:
1026:
1024:
1010:
1001:
995:
994:
976:
968:Armstrong, E. H.
964:
933:Armstrong, E. H.
929:
920:
919:
899:
890:
889:
869:
860:
859:
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803:
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755:
753:
751:
731:
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724:
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720:
695:
684:
678:
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647:
638:
634:Space Telegraphy
630:
623:
617:
616:
596:
569:
545:
525:
376:Western Electric
366:General Electric
338:General Electric
304:Electrical World
281:
270:thermionic valve
263:
257:
229:
220:
21:
2720:
2719:
2715:
2714:
2713:
2711:
2710:
2709:
2685:
2684:
2683:
2678:
2657:
2643:Mullard–Philips
2616:
2567:Photomultiplier
2427:
2408:Suppressor grid
2371:
2366:
2336:
2331:
2269:
2184:audio and video
2169:
2136:
2068:
2005:
1933:
1914:Photomultiplier
1839:
1767:
1715:Quantum circuit
1623:
1617:
1559:Avalanche diode
1545:
1457:
1450:
1339:
1328:
1321:
1316:
1248:
1203:
1174:
1166:
1151:Privateline.com
1144:
1136:
1121:
1106:
1094:
1083:
1081:Further reading
1078:
1066:
1065:
1061:
1040:
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746:(1665): 348–352
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428:
372:Second row (B):
356:Bottom row (D):
346:
334:Irving Langmuir
277:
259:
253:
246:
245:
244:
243:
232:
231:
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206:note magnifiers
197:
141:
129:radio receivers
48:from 1908. The
35:
28:
23:
22:
15:
12:
11:
5:
2718:
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2599:
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2572:Selectron tube
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2263:Wollaston wire
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2044:Selectron tube
2041:
2036:
2034:Magic eye tube
2031:
2026:
2021:
2015:
2013:
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2003:
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1966:
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1603:Schottky diode
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1229:
1219:(3): 261–293,
1202:. Reprint of
1164:
1159:
1142:
1135:
1134:External links
1132:
1131:
1130:
1124:
1119:
1104:
1082:
1079:
1077:
1076:
1059:
1030:
996:
985:(4): 685–697.
970:(April 1997).
947:(9): 215–247.
921:
915:978-0470409749
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576:magazine, 1916
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362:Third row (C):
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149:radio receiver
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2638:Marconi-Osram
2636:
2634:
2631:
2629:
2626:
2625:
2623:
2619:
2613:
2612:Fleming valve
2610:
2608:
2607:Williams tube
2605:
2603:
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2418:Glowing anode
2416:
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2388:Work function
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2325:mercury relay
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2148:Potentiometer
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2064:Williams tube
2062:
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1883:Fleming valve
1881:
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1710:Photodetector
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1679:
1678:Memtransistor
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1327:Semiconductor
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1120:9780262082983
1116:
1113:, MIT Press,
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809:Lee de Forest
802:
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785:9780080524054
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534:Lee de Forest
531:
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482:Western world
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274:Fleming valve
271:
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125:Fleming valve
122:
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117:dynamic range
114:
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99:
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91:
87:
83:
79:
75:
71:
67:
66:Lee de Forest
63:
59:
51:
47:
43:
39:
33:
19:
2700:Vacuum tubes
2577:Storage tube
2471:Beam tetrode
2445:
2403:Control grid
2398:Space charge
2082:Cold cathode
2049:Storage tube
1939:Vacuum tubes
1888:Neutron tube
1863:Beam tetrode
1857:
1845:Vacuum tubes
1430:Power MOSFET
1258:
1254:
1216:
1212:
1182:
1178:
1155:the original
1150:
1126:
1109:
1095:
1069:
1062:
1053:
1049:
1021:. Retrieved
1016:
1012:
999:
982:
978:
944:
940:
904:
874:
844:
808:
801:
789:. Retrieved
775:
765:
748:. Retrieved
743:
739:
729:
717:. Retrieved
703:
680:
671:. Retrieved
659:
655:
632:
621:
601:
573:
560:around 1920.
514:
490:
479:
468:
464:
437:
429:
420:
411:
408:
404:
401:
396:
392:
389:
382:Top row (A):
381:
371:
361:
355:
330:
326:
322:regeneration
317:
309:oscilloscope
302:
288:
284:
247:
239:
235:
205:
198:
189:
184:
174:
158:
113:residual gas
110:
57:
55:
2582:Sutton tube
2393:Hot cathode
2248:Transformer
1990:Sutton tube
1830:Charge pump
1683:Memory cell
1613:Zener diode
1575:Laser diode
1458:transistors
1340:transistors
656:Trans. AIEE
532:, built by
501:solid state
497:vacuum tube
493:electronics
475:World War I
368:by Langmuir
165:radio waves
84:: a heated
62:vacuum tube
46:vacuum tube
18:Audion tube
2689:Categories
2597:Trochotron
2527:Iconoscope
2517:Compactron
2512:Charactron
2456:Acorn tube
2320:reed relay
2310:Parametron
2243:Thermistor
2221:resettable
2180:Connector
2141:Adjustable
2117:Nixie tube
2087:Crossatron
2054:Trochotron
2029:Iconoscope
2024:Charactron
2001:X-ray tube
1873:Compactron
1853:Acorn tube
1810:Buck–boost
1731:Solaristor
1593:Photodiode
1570:Gunn diode
1566:(CLD, CRD)
1348:Transistor
1268:expensive.
1013:Radio News
885:1579584640
855:0521835267
819:0934223238
791:January 7,
750:21 October
719:January 7,
612:9051991452
582:References
554:oscillator
505:transistor
491:In modern
486:transistor
448:barretters
442:including
147:An Audion
82:electrodes
78:glass tube
2562:Phototube
2557:Monoscope
2552:Magnetron
2547:Magic eye
2537:Kinescope
2481:Pentagrid
2283:Capacitor
2127:Trigatron
2122:Thyratron
2112:Neon lamp
2039:Monoscope
1919:Phototube
1903:Pentagrid
1868:Barretter
1753:Trancitor
1748:Thyristor
1673:Memristor
1598:PIN diode
1375:(ChemFET)
1257:: 41–44.
1023:August 3,
673:March 30,
440:detectors
289:In 1914,
153:de Forest
2662:Examples
2542:Klystron
2522:Eidophor
2497:Additron
2461:Nuvistor
2305:Inductor
2275:Reactive
2253:Varistor
2233:Resistor
2211:Antifuse
2097:Ignitron
2092:Dekatron
1980:Klystron
1969:Gyrotron
1898:Nuvistor
1815:Split-pi
1701:(MOS IC)
1668:Memistor
1426:(MuGFET)
1420:(MOSFET)
1392:(FinFET)
1280:battery.
1199:47501618
772:"Triode"
700:"Audion"
550:AM radio
444:coherers
293:student
181:gridiron
121:detector
96:, and a
90:tantalum
86:filament
50:filament
2653:Russian
2476:Pentode
2466:Tetrode
2206:Ferrite
2174:Passive
2165:Varicap
2153:digital
2102:Krytron
1924:Tetrode
1909:Pentode
1763:Varicap
1744:(3D IC)
1720:RF CMOS
1624:devices
1398:(FGMOS)
1329:devices
961:2116636
336:in the
276:patent
240:(right)
183:(hence
177:patents
139:History
106:amplify
44:Audion
2487:Nonode
2451:Triode
2446:Audion
2423:Getter
2238:Switch
1929:Triode
1893:Nonode
1858:Audion
1738:(SITh)
1622:Other
1589:(OLED)
1551:Diodes
1502:(LET)
1484:(FET)
1456:Other
1404:(IGBT)
1381:(CMOS)
1368:BioFET
1363:BiCMOS
1197:
1117:
1099:,
959:
912:
882:
852:
816:
782:
710:
609:
495:, the
456:galena
450:, and
433:triode
236:(left)
169:vacuum
74:triode
58:Audion
42:Triode
2633:RETMA
2441:Diode
2433:Types
2413:Anode
2315:Relay
2288:types
2226:eFUSE
1997:(TWT)
1985:Maser
1976:(IOT)
1965:(CFA)
1954:(BWO)
1878:Diode
1825:SEPIC
1805:Boost
1758:TRIAC
1727:(SCR)
1690:(MOV)
1664:(LEC)
1583:(LED)
1542:(UJT)
1531:(SIT)
1525:(PUT)
1468:(BJT)
1437:(TFT)
1413:LDMOS
1408:ISFET
1195:S2CID
1175:(PDF)
1009:(PDF)
975:(PDF)
957:S2CID
760:site.
250:diode
98:plate
92:), a
70:diode
68:as a
2258:Wire
2216:Fuse
1800:Buck
1653:(IC)
1641:DIAC
1577:(LD)
1446:UMOS
1441:VMOS
1358:PMOS
1353:NMOS
1338:MOS
1115:ISBN
1025:2014
910:ISBN
880:ISBN
850:ISBN
814:ISBN
793:2013
780:ISBN
752:2023
721:2013
708:ISBN
675:2021
607:ISBN
416:gain
412:plio
397:tron
393:keno
185:grid
131:and
94:grid
56:The
2648:JIS
2628:RMA
1820:Ćuk
1255:QST
1221:doi
1187:doi
987:doi
949:doi
664:doi
187:).
151:by
2691::
2194:RF
1943:RF
1253:.
1215:,
1211:,
1193:,
1183:85
1181:,
1177:,
1149:.
1054:64
1052:.
1048:.
1033:^
1015:.
1011:.
983:85
981:.
977:.
955:.
943:.
939:.
924:^
894:^
864:^
828:^
774:.
744:64
742:.
738:.
702:.
688:^
660:25
658:.
654:.
642:^
631:,
589:^
477:.
446:,
2361:e
2354:t
2347:v
1945:)
1941:(
1311:e
1304:t
1297:v
1223::
1217:3
1189::
1027:.
1017:9
993:.
989::
963:.
951::
945:3
918:.
888:.
858:.
822:.
795:.
754:.
723:.
677:.
666::
615:.
34:.
20:)
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