Dating fender tube amps by serial number part 5
In it's simplest form a vacuum tube can be created to operate as a diode: a device that conducts current only in one direction.
A third element called a "control grid" can be added to the design which provides the ability to amplify a signal.
Many musicians prefer to play vintage Fender, Marshall and Gibson amps.
The speaker lineup and the output transformer were based on the Fender Super amp of the time and the circuit based on the Fender Vibrolux of the time, with no presence control and only one 12AX7 tube for the tremolo effect.
It sported typical "brownface" cosmetics, with brown "Tolex" covering (introduced by Fender in 1959), and wheat-colored speaker cloth.
From 1969 to 1983 the date code was after the serial number.
From 1984 to 1992 the model number was first, then the date code, then the serial number.
For most purposes, the vacuum tube has been replaced by the much smaller and less expensive transistor, either as a discrete device or in an integrated circuit.