What was a Hybrid Radio?

Answer 1

One form of hybrid radio, appearing in the late 1950s, used valves (vacuum tubes) and transistors together.

Early transistors worked fine at audio frequencies, and were much more efficient, using much less battery power. They could not perform at radio frequencies, however.

Vacuum tubes had been used at radio frequencies for many years, but the push to miniaturise them led to lower performance. Even the subminiature types (about the diameter of a cigarette) still used a lot of battery power to operate.

The hybrid radio used valves in the radio frequency end (usually three) and transistors in the audio end (usually two).

This design made best use of the advantages of valves and transistors.

Transistor development was rapid, and all-transistor radios appeared soon after hybrid sets were marketed. They were only available as battery portables.

Hybrid sets are among the rarest of mass-produced radios.