Capacitor C20 should be with air dielectric. Vernier of any kind would
be useful with the capacitor.
Receiver has potentiometer R9 for audio
signal. It is useful part of any regenerative receiver where some
signals are at the hearing border but another very loud. Capacitor
C24 (with help of a switch) grounded first grid of the audio tube.
It is decreased noise in the headphones at CW- reception. Any
Audio Transformer from an old tube receiver may be used for the
2 shows design of the inductors L1… L12. All inductors were wound on empty
gun cartridges in diameter 20- mm. Table 1 shows data for the inductors.
3 shows design of the receiver. At the top of the inductors trimmer capacitors
are installed. It is very conveniently for tuning of the receiver
at amateurs bands. Figure 4 shows the trimmer capacitors at top of
The receiver is easy to tuning and fun for operation. At good parts and
inductors made according to the Table 1 the receiver works straight
away and at the frequencies close to amateur bands.