It is simple experimental receiver that was made on
two tubes- twin triodes. The receiver was tuned to 80- meter amateur
band. Schematic of the receiver is shown on Figure 1.
Video of the receiver is:
Audio of the receiver is:
It is usual DC Receiver with phase suppression of the
second side band. Book “Direct Conversation Technique
for Radio Amateurs” (Antentop 01- 2015,
p. 88) gives information how to tune and adjust such receiver.
Figure 2 shows design of the
receiver. Receiver consumes current 4.3-mA. VFO consumes current
2 mA. Figure 3
shows the current. Figure 4 shows shape of the RF signal of the VFO.
Receiver could work fine with antenna in several meter length.
It is possible use players low – ohmic
headphones turned on through transformer or high-ohmic
(2x 2000-Ohm) phones turned on to tube plate through capacitor
Figure 4 Shape of the RF Signal of the VFO