FETs and Tubes

As mentioned earlier in this book, modern electronics would not be practical without amplification (see pages 165 and 166 if necessary), because this allows a large number of operations to be performed in series, without any total loss of signal strength from various resistances. The first practical amplifying device 

Instead of being stopped by the plate, a large hole can be drilled in the plate, and many of the high speed electrons will go through it. This electron ray can be directed toward a transparent fluorescent screen, in an oscilloscope or TV picture tube, as was described in Chapter 8. 

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