IEEE SPECTRUM Magazine advertisment of the past placed in IEEE SPECTRUM November 2015 on Beam Power Amplifier Tubes or Operational Amplifiers of the past

IEEE SPECTRUM Magazine advertisment of the past placed in IEEE SPECTRUM November 2015 on Beam Power Amplifier Tubes or Operational Amplifiers of the past. The article mentions briefly in the 1930's and 1940's, Unites States of America and the Radio Corporation of America had amateur radio operators and ham-radio operators and has been utilised by English engineer, D.T.N. Williamson in 1947. These tubes are still made by Russia and China and are available to audiophiles and people all over the world.

Junt Hoong Chan worked on the Operational Amplifier as his research project for his final year thesis in 1997 at the University of Birmingham, Birmingham, United Kingdom. During the research into Operational Amplifiers, I found that the Amplifiier Tubes were utilised in the past as Operational Amplifiers. They were utilised in the war in 1939 - 1945 by the German army in calculations and trajectory and to fire weapons, for example, in the Battleship Bismark and Tirpitz and I believe in the whole of the German army then. They are accurate in targetting and trajectory calculations of the era then. Are they still utilised today? Japan once had a Mikoyan MIG-25 Foxbat that landed on it's shores. It was examined and it was found that they utilised these Amplifier Tubes or Operational Amplifiers. For a Plane that could perform at Mach 3 the Speed of Sound, utilising Amplifier Tubes, it's a super achievement then. Thank you all for the time in reading this small article. It was part of the understanding then during my research into a Power Electronics Project utilising Operational Amplifiers. From Junt Hoong Chan MIET MIEEE CEng.