“Wireless” receivers were initially all tuned radio frequency (TRF) types. The superheterodyne circuit was not invented until Major Edwin Armstrong developed the concept during World War 1. Superhet receivers are more complex than TRF receivers but have many advantages where high performance is required.
By contrast, TRFs were traditionally used where cost, non-critical performance and simple circuit design were important. Many TRF radios are easy to operate but those using regeneration require operating skills that many non-technical listeners find hard to acquire. Although TRFs are rarely seen these days as domestic receivers, they are still used in the form of super-regenerative receivers for such things as garage door openers.
Most receivers manufactured from the mid-1930s onwards were superhets but manufacturers occasionally produced a simple, cheap TRF set to satisfy the low-cost end of the market. The Astor GR/GRP is one such example.
The Astor Football (GR, GRP)
The Astor “Football”, as it is affectionately known, is a small, 3-valve, economy mantel broadcast receiver produced around 1948. “Football” wasn’t its official name but the cabinet is around the same size and shape as an Australian Rules football, hence the unofficial nickname given to the set by users and collectors. It was intended for use as a kitchen or bedroom radio; anywhere radio signals were strong.
The Football’s bakelite cabinet came in a few colours, with brown and cream being the most common. The cabinet is made in two parts, which are separated by undoing three screws, two underneath the cabinet through rubber buffers and the other through the back. However, the design leaves something to be desired, as the thread that goes through the cabinet to the rear retaining nut fouls the 6G8G valve and makes it difficult to replace the back.
To transport the set, four fingers are inserted through the back section of the case and it is then carried that way. However, an antenna is required for decent reception and the 5.2-
metre permanently connected antenna doesn’t lend itself to easy portability.