Designed for valve (vacuum tube) radio enthusiasts, or anyone who would like to try the nostalgic approach to shortwave listening.

Despite continuing advances in semiconductor technology, the humble valve (vacuum tube) refuses to totally stand aside in favour of modern technology. Audio equipment having the true "valve sound" has a strong following, as do olde worlde electronic music equipment and radios. I [the author] wish I could say that I do not remember the days when this type of receiver was the normal introduction to the shortwave bands, but it is very much the type of set that I built as a lad in the 1960s. I still remember the HAC two-valve set with its pre-war valves the size of 100W light bulbs, and the RCS "Telstar" with its miniature "acorn" valves that really were more or less acorn shaped.

The design featured here follows along the same general lines as these sets, with its simple chassis and front panel method of construction and regenerative detector. It covers an approximate tuning range of 5MHz to 13MHz using a simple home constructed tuning coil. This provides coverage of several popular shortwave broadcast bands. Sets of this type were almost invariably powered from batteries, and required about 90 volts for the main supply and around 1·5 to 6 volts for the heaters. These were respectively the HT (high tension) and LT (low-tension) supplies. Suitable HT batteries are no longer produced, but the design featured here will work well using three or four “bog standard” PP3 size 9V batteries wired in series. A single 1·5V cell is needed to power the heaters. By the standards of battery-powered valve sets the unit is quite economic to run.