Voltage to Current Convertor When driving the input (base) of a transistor gain stage: you must
convert the input voltage to a current by using a voltage to current convertor--a
resistor.
Current to Voltage Convertor When deriving a voltage from the collector of a transistor amplifier
stage: you convert the output (collector) current into a voltage by using
a Current to Voltage convertor in the collector circuit--you guessed it--a
resistor.
Resistance
is Determined partially by Composition, and is inversely proportional
to
Cross Sectional Area
Notice
Also that Resistance is proportional to Length
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