Because vacuum tubes become hot and most are made of glass, use caution
while removing or replacing them. Use vacuum tube pullers or at least wear some
type of hand protection.
Wavelength is the distance in space occupied by one cycle of a radio wave at any given instant. If a
radio wave could be frozen in time and measured, the distance from the leading edge of one cycle to the
leading edge of the next cycle would be the wavelength. Wavelength varies from a few hundredths of an
inch at the high frequencies to many miles at extremely low frequencies. Common practice is to express
wavelength in meters. The Greek letter lambda ( ) is used to signify wavelength. Formulas for
wavelength, period, and velocity are shown below.
You can find more information on wavelength, frequency, period, and velocity in NEETS, Module
10, Introduction to Wave Propagation, Transmission Lines, and Antennas.