- published: 03 Nov 2013
- views: 2975
The Audion is an electronic amplifying vacuum tube invented by Lee De Forest in 1906. It was the forerunner of the triode, in which the current from the filament to the plate was controlled by a third element, the grid. A small amount of power applied to the grid could control a larger current from the filament to the plate, allowing the Audion both to detect radio signals (that is, make them audible) and to provide amplification. However, De Forest's Audion is quite distinct from the true vacuum triode in that it is not capable of linear amplification.
It had been known since the middle of the 19th century that gas flames were electrically conductive, and early wireless experimenters had noticed that this conductivity was affected by the presence of radio waves. De Forest found that gas in a partial vacuum heated by a conventional lamp filament behaved much the same way, and that if a wire were wrapped around the glass housing, the device could serve as a detector of radio signals. In his original design, a small metal plate was sealed into the lamp housing, and this was connected to the positive terminal of a 22 volt battery via a pair of headphones, the negative terminal being connected to one side of the lamp filament. When wireless signals were applied to the wire wrapped around the outside of the glass, they caused disturbances in the current which produced sounds in the headphones.
Communication 1928 Devry School Films; Telephone, Telegraph, Audion Tube... Animations
A small bit of Radio History, Lee De Forest Audion, Marconi
40m regen tube receiver working ssb with 6V / 40m Audion Empfänger, Einseitenbandmodulation
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Making a spherical audion vacuum tube part1
Making a spherical audion vacuum tube part4
OK1FPQ: Radio Audion Tubes 2x 12Z1L
50's home made regenerative audion tube radio from Hungary
Making a spherical audion vacuum tube part 2
Making a spherical audion vacuum tube part 3
Dear mother I am lost and the damage has been done.
I’m in love with my old century fix and this needle can’t be wrong,
But I wonder?
Where do we go from here because we’re never coming home?
The sequel to this nightmare lasts forever, forever.
One last goodnight, with this painted picture in our minds the voice inside that sings tonight.
One last goodnight, with this painted picture in our minds the voice inside that sings tonight.
I’m not scared at all, so let’s walk away.
I’m not scared at all, so now walk away.
Dear mother now beyond the grave you’re the soul that wants me.
Front row with a cigarette, you’re the ghost that haunts me,
But I wonder?
I’m too fucked up to come home,
I swear this heart was made of stone,
I won’t pretend that everything’s alright when it’s not.
One last goodnight, with this painted picture in our minds the voice inside that sings tonight.
One last goodnight, with this painted picture in our minds the voice inside that sings tonight.
I’m not scared at all, so let’s walk away.
I’m not scared at all, so now walk away.
Wake me now drive faster, make me now a disaster,
Take me now live after and walk away.2x
Can you design living through hell and back again?
It’s the life that’s killing you walk away friend.
Can you design living through hell and back again?
It’s the life that’s killing you walk away WALK AWAY!!!
One last goodnight, with this painted picture in our minds the voice inside that sings tonight.