
Glossary
180"out-of-phase
when two identical sinewaves are up-
side-down
with respect to each other.
active
a device which controls current is said to be ac-
tive.
ampere
standard unit to measure electrical current.
Abbreviated to amp. Symbolised by A.
amplitude
the amplitude of an a.c. signal is the differ-
ence
in voltage between its middle or common point and
the peak voltage.
analogue
one of the two operating modes of a transis-
tor, in which a variable tiny base current is used to
control a large
collector
current.
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