Superheterodyne receiver
In electronics, a superheterodyne receiver (often shortened to superhet) uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency. It was invented by US engineer Edwin Armstrong in 1918 during World War I. Virtually all modern radio receivers use the superheterodyne principle. At the cost of an extra frequency converter stage, the superheterodyne receiver provides superior selectivity and sensitivity compared with simpler designs.
History
Background
"Superheterodyne" is a contraction of "supersonic heterodyne", where "supersonic" indicates frequencies above the range of human hearing. The word heterodyne is derived from the Greek roots hetero- "different", and -dyne "power". In radio applications the term derives from the "heterodyne detector" pioneered by Canadian inventor Reginald Fessenden in 1905, describing his proposed method of producing an audible signal from the Morse code transmissions of the new continuous wave transmitters. With the older spark gap transmitters then in use, the Morse code signal consisted of short bursts of a heavily modulated carrier wave, which could be clearly heard as a series of short chirps or buzzes in the receiver's headphones. However, the signal from a continuous wave transmitter did not have any such inherent modulation and Morse Code from one of those would only be heard as a series of clicks or thumps. Fessenden's idea was to run two Alexanderson alternators, one producing a carrier frequency 3 kHz higher than the other. In the receiver's detector the two carriers would beat together to produce a 3 kHz tone thus in the headphones the Morse signals would then be heard as a series of 3 kHz beeps. For this he coined the term "heterodyne" meaning "generated by a difference" (in frequency).
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Food For The Masses
by: SpearheadI love family
'Cause family brings inspirations
One love to you and peace to all the nations
Aztlan the Puerto Rican and Jamaican
The African the Maori, Kouri and the Haitian
On the chocolate reservation
I'll take a hit and then pass the information
To the left hand side and
Keep providin', pride and
Sustenance and guidance
Mass Hysteria fools breaking down the barrier
Militant cliques big up the area
Put your fist in the air now
Show me that cha care now
And that cha really know how
Don't get thee behind me Satan
I'll keep thee in front so I can kick thee in the ass and
Assassinate all your wicked inventions
Your new world order and your global intentions
Not to mention the department of corrections
Makin' money off of people in detention
Doin' time for possessions
Countin' the days in the dark they buildin' up aggressions
Progressions all the dirty lessons
In the belly of the beast only God hears confessions
Geronimo Pratt's still sittin' in the cellar
Done as many years as they did Mandela
Parole board wanted to know are you remorseful
How could I be because I didn't do the crime yo
Y'alls the Motha fucka's that's guilty
Lockin' me in solitary eight years of filthy
Kill the messenger, you can't kill the message
Yo I'm bringin' food for the masses
For the Masses for the masses
Mental food food for the masses
For the masses for the masses for the true for the true
For the Masses for the masses
Mental food, food for the masses
For the masses for the masses for the true for the true
So let's eat have a seat
Call the Maitre D'
Commencin' with the rythm
I get open on the beat
Let 'em say what they say about the way that we be
It's the year two triple O
They can't stop we
Aw'ight, so let's see how the book unfolds
I write 'cause half the story has never been told so
No one can stop it the whole world's droppin' out the socket
Blowin' up, like NASA when I rock it
The high tech ways of the civilized man
Can't stand my people but ya love the sun tan
Fly the space shuttle like dancer and prancer
You nuke the north pole now you got skin cancer
The answer you see I'm fly like Lufthansa
You can Value it but you takin' big chances
On crashes. Change your name like Cassius
The classes be making food for the masses
Then shift to a speed that's common for the listeners
MC's and wanna be street politicians
In competition with the envious visions
They chasin' paper dollars to a pop chart prison
But listen this isn't me against you
'Cause the whole world's checking out the things that we do
Ya sold your soul to the Saint Ide's brew
That's aw'ight I like the Sprite in you
For the Masses for the masses
Mental food food for the masses
For the masses for the masses for the true for the true
For the Masses for the masses
Mental food, food for the masses