Fig. 22.23 Two other methods of antenna coupling: (a) a relatively high-inductance
primary coil (L,) augmented if necessary by top capacitance (C
3
); (b) small series
capacitance
be poor at the highest frequencies, at which L
2
C
2
is most out of tune
with the antenna, so a small capacitor C
3
is sometimes included to
help things along. Another method (Fig. 22.236) has the merit of
simplicity and of ensuring that whatever antenna is used the
capacitance it adds to the tuned circuit must be less than C
4
. And the
range of signal strength brought in by antennas of different sizes is to
some extent levelled out, for the larger it is the more it
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