Page 55 - Build Your Own Transistor Radios a Hobbyists Guide to High-Performance and Low-Powered Radio Circuits
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FIGURE 3-25 Tie points .
To mount the speaker, antenna coil, or vector or perf board, spacers are needed.
The ones shown in Figure 3-26 use 4-40 threads, but other spacer sizes may be
used.
FIGURE 3-26 Spacers.
Generally, an oscillator coil, which has a tapped primary winding and a secondary
winding, is used for the local oscillator circuit for superheterodyne receivers.
However, some have an inductance value suitable for an RF amplifier circuit. See
the oscillator coil in Figure 3-27, which is generally used with a 60-pF variable
capacitor for an oscillator circuit but is also suitable for use with a loop antenna.
