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 ==Solution==
-[[File:Distributed amplifier principle.jpg|thumb|400px|right|Distributed amplifier principle]]
+[[File:Distributed amplifier principle.png|thumb|400px|right|Distributed amplifier principle]]
-In a distributed amplifier, several stages are connected together to form what in effect
+In a distributed amplifier, several stages are connected together to form what in effect is a "transmission line with gain".
-is a "transmission line with gain". The gain is the sum (not the product)
+The gain is the sum (not the product) of the gains of the stages, whereas the bandwidth of a distributed amplifier is the bandwidth of each of the stages.
-of the gains of the stages, whereas the bandwidth of a distributed amplifier is
-the bandwidth of each of the stages.
 Thus, it is possible to construct an amplifier with a gain of 100 and a rise time of 3 ns
-by using ten instances of the ×10, 3 ns amplifier from the earlier example connected to
+by using ten instances of the ×10, 3 ns amplifier from the earlier example connected to form a distributed amplifier.
-form a distributed amplifier.
-The key difference between a distributed conventional cascaded-stage amplifier is that
+The key difference between a distributed conventional cascaded-stage amplifier is that in the former,
-in the former, the input of  each stage is the original signal, not the output of a
+the input of  each stage is the original signal, not the output of a previous stage, thus eliminating
-previous stage, thus eliminating the cumulative degradation of rise time that occurs in
+the cumulative degradation of rise time that occurs in cascaded stages.
-cascaded stages.
-One of the most important challenges when building distributed amplifiers is avoiding
+One of the most important challenges when building distributed amplifiers is avoiding reflections in the signal path.
-reflections in the signal path.  For example, when the input signal reaches the input
+For example, when the input signal reaches the input of one stage, parasitic capacitance of that stage must not
-of one stage, parasitic capacitance of that stage must not cause an impedance discontinuity
+cause an impedance discontinuity in the signal path, which would cause reflection.
-in the signal path, which would cause reflection.
 [[File:Tek 581 vertical output amp.png|thumb|right|400px| [[581|Tektronix 581]] distributed vertical amplifier schematic (click to enlarge)]]
 Since eliminating the parasitic capacitance is not possible, the approach is usually to
@@ Line 61: / Line 56: @@
 ==History==
 [[File:Tek513-dist-amp.jpg|thumb|250px|right|Symmetrical distributed amplifier in [[513]] scope]]
-The idea of a distributed amplifier goes back to British Patent 460,562 by W.S. Percival in 1936.
+The idea of a distributed amplifier goes back to [[Patent GB 460562A|British Patent 460,562 by W.S. Percival in 1936]].
-In 1948, Ginzton, [[Bill Hewlett|Hewlett]], Jasberg and Noe published a paper on distributed amplifiers in the Proceedings of the IRE, first using the term "distributed amplifier".  Around the same time, Hewlett met [[Logan Belleville]] of Tektronix in a Portland restaurant and described the concept on a napkin.  In the fall of 1948, [[Howard Vollum]] and [[Dick Rhiger]] built a 6 ns rise time distributed amplifier under a US government contract (for radar applications).  The prototype was attached externally to an early [[511]] oscilloscope.
+In 1948, Ginzton, [[Bill Hewlett|Hewlett]], Jasberg and Noe published a paper on distributed amplifiers in the Proceedings of the IRE, first using the term "distributed amplifier".  Around the same time, Hewlett met [[Logan Belleville]] of Tektronix in a Portland restaurant and described the concept on a napkin.
+In the fall of 1948, [[Howard Vollum]] and [[Dick Rhiger]] built a 6 ns rise time distributed amplifier under a US government contract (for radar applications).  The prototype was attached externally to an early [[511]] oscilloscope.
 Vollum, Belleville and Rhiger went on to design the 50 MHz [[517]] oscilloscope incorporating a distributed vertical amplifier.
@@ Line 94: / Line 92: @@
 == Reading ==
-* W. S. Percival, British Patent Specification No. 460,562, ''Improvements In and Relating to Thermionic Valve Circuits'', applied for, July 24, 1936, granted January 1937
+* [[wikipedia:Distributed_amplifier|Distributed Amplifier]] @ Wikipedia
-* E. L. Ginzton, W. R. Hewlett, J. H. Jasberg, J. D. Noe, “Distributed Amplification”, Proceedings of the IRE, pp 956- 969, August 1948.
+* W. S. Percival, [[Patent GB 460562A|British Patent Specification No. 460,562, ''Improvements In and Relating to Thermionic Valve Circuits'']], Filed 24 Jul 1936, granted 2 Jan 1937
-* [http://w140.com/US2930986.pdf US Patent 2,930,986]: [[John Kobbe|J. R. Kobbe]] and [[Bill Polits|W. J. Polits]], "Distributed Amplifier". Applied 29 Feb 1956, granted 29 Mar 1960.
+* E. L. Ginzton, W. R. Hewlett, J. H. Jasberg, J. D. Noe, “Distributed Amplification”, Proceedings of the IRE, pp 956-969, August 1948.
-* [http://en.wikipedia.org/wiki/Distributed_amplifier Wikipedia: Distributed Amplifier]
+* [[John Kobbe]] and [[Bill Polits]], [[Patent US 2930986A|US Patent 2,930,986, ''Distributed Amplifier'']]. Filed 29 Feb 1956, granted 29 Mar 1960.
 * [[John Addis]], ''Good Engineering and Fast Vertical Amplifiers'', in Jim Williams (Ed.), ''Analog Circuit Design: Art, Science and Personalities'' (1991),  p.110
+* G.Nikandish, R.Staszewski and A.Zhu, ''[https://hertz.ucd.ie/publications/DA_Review.pdf The (R)evolution of Distributed Amplifiers: From Vacuum Tubes to Modern CMOS and GaN ICs]''. IEEE Microwave Magazine Vol. 19 Issue 4, June 2018, p.66+
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