Audion
The Audion was an electronic amplifying vacuum tube invented by American electrical engineer Lee De Forest in 1906. It was the first triode, consisting of a partially evacuated glass tube containing three electrodes; a heated filament, a grid, and a plate. It is important in the history of technology because it was the first widely used electrical device which could amplify; a small electrical signal applied to the grid could control a larger current flowing from the filament to plate.
Unlike later vacuum tubes, the primitive Audion had a small amount of gas in the tube, thought to be necessary by De Forest, which limited the dynamic range and gave it nonlinear characteristics and erratic performance. Originally developed as a radio receiver detector by adding a grid electrode to the Fleming valve, it found little use until its amplifying ability was recognized around 1912 by several researchers, who used it to build the first amplifying radio receivers and electronic oscillators. The many practical applications for amplification motivated its rapid development, and the original Audion was superseded within a few years by improved versions with higher vacuum, developed by Irving Langmuir at GE and others. These were the first modern "hard vacuum" triodes.
Podcasts:
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by Leonard Cohen
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by Die Happy
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by Jennifer Warnes
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by Vern Gosdin
Way Down Deep
by: Leonard Cohen(Leonard Cohen/Sharon Robinson)
Baby, I've been waiting
I've been waiting night and day
I didn't see the time
I waited half my life away
There were many invitations
And I know you sent me some
But I was waiting
For the miracle to come
I know you really loved me
But, you see, my hands were tied
I know it must have hurt you
It must have hurt your pride
To stand beneath my window
With your bugle and your drum
While I was waiting
For the miracle to come
You wouldn't like it baby
You wouldn't like it here
There's not much entertainment
And the critics are severe
The Maestro says it's Mozart
But it sounds like bubble gum
When you're waiting
For the miracle to come
CHORUS
Waiting for the miracle
There's nothing left to do
I haven't been this happy
Since the end of World War II
Nothing left to do
When you know that you've been taken
Nothing left to do
When you're begging for a crumb
Nothing left to do
When you've got to go on waiting
For the miracle to come
I dreamed about you, baby
It was just the other night
Most of you was naked
But some of you was light
The sands of time were falling
>From your fingers and your thumb
And you were waiting
For the miracle to come
Baby, let's get married
We've been alone too long
Let's be alone together
Let's see if we're that strong
Let's do something crazy
Something absolutely wrong
While we're waiting
For the miracle to come
CHORUS
When you've fallen on the highway
And you're lying in the rain
And they ask you how you're feeling
Of course you say you can't complain
If you're squeezed for information
That's when you've got to play it dumb
You just say you're out there waiting
For the miracle to come