Output matching network for most high-powered amplifiers should normally consist of
the T type, rather than the PI type. PI matching networks for high powered amplifiers
sometimes result in unrealistic component values when matching for the higher
operating frequencies encountered into a 50 Ω load. Indeed, T networks are capable
of much higher-frequency operation before this becomes a major problem. Both T and
PI networks can be used, however, if the output impedance of the transistor is higher
than its load.