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If you ever wondered how those early radio and wireless receivers
from the 1920's worked, then why not build your very own. Or
maybe you just want to learn how valves work, but are afraid to
tackle a mains powered set, then try this battery powered kit,
it is a great way to learn a new hobby!
One, two, three and four valve (tube) receivers based on original
1920's and 1930's designs such as the
"Twinplex".
In
1912, the brilliant American inventor, Edwin Howard Armstrong,
discovered a method of feeding the signal from the Audion's
(tube) plate back through its grid, which increased the
amplification capabilities of the circuit many times. He found
that increasing this feedback caused the valve (tube) to
oscillate at radio frequencies. This valve (tube) made selective
reception and amplification of radio signals not only possible,
but easy. Armstrong's invention was unique in that it performed
three functions in one circuit: it was a rectifying detector, a
positive feedback amplifier, and a oscillator all in one
envelope. This stunning invention, known as the
"regenerative detector", raised the radio receiver to
a level that made broadcast radio reception accessible to the
masses of the world.
We
offer four radio kits based on Armstrongs
original designs, which were popular to constructors
through the mid 1920's and into the 1930's.>
Easy assembly, for example no coils to wind - that has
already been done for you! And simple to follow
instructions with both schematics and wiring diagrams!
You get a manual, all the parts including valves, sockets,
jack plugs, tuning capacitors, coils, resistors, wire, nuts and
bolts etc, and we even include an earpiece.
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