In the SPRAT # 67
(SPRAT is the journal of the G- QRP- Club) was published a circuit
of a tube DC receiver. I made this G0ILL receiver and enjoyed
of it perfect reception. Later I modified the receiver to transceiver.
It was tried several versions of the transceiver. The final one
was made on a PCB- board 200 x 240- mm with plug- in inductors
in old tube sockets. So, the transceiver was tested on all amateurs
HF- Bands. The frequency stability was not good enough at 24 and
28- MHz but was good on the lower bands. Figure 1
shows the schematic of the tube DC transceiver.
RX RF Amplifier made on V1. V4
is mixer. Audio Amplifier made on V7. Audio amplification is adjusted
by R16. RF amplification is adjusted by R5.
VFO and Doubler made on V2. Circuit
L3C3C2 is tuned on frequency twice below the used.
Circuit L6C7 is tuned on main
frequency. V5 is driver, V6 is PA. Transceiver works at QSK mode,
i.e. to turn the transceiver for TX just press key. Cathodes of
the driver and PA are grounded, RL1 grounded RX antenna.