This one-tube circuit appeared in the British Practical Wireless 80 years ago this month, August 1943. It made the best of wartime parts shortages, since the single tube, a P220, did double duty as both RF and AF amplifier. A fixed crystal was used as detector.

It had been sent to the magazine by R.J. Amblin of Bath, England, who reported that with 18 volts of anode (plate) voltage, it gave good volume through the headphones, and he was able to pull in the BBC Home Service with as little as 1.5 volts. For normal listening, he left it at 4.5 volts, which proved quite satisfactory.