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Materi Tentang TV

BAB I
PEMELAJARAN

a. Uraian Materi
1. DIAGRAM BLOK PENERIMA TV

Gambar 1. Diagram Blok Penerima TV Hitam Putih


Gambar 2. Diagram Blok Penerima TV Berwarna

Sebelum kita mempelajari prinsip kerja penerima TV, ada baiknya mengetahui sedikit tentang perjalanan objek gambar yang biasa kita lihat dilayar TV. Gambar yang kita lihat adalah hasil produksi dari sebuah kamera. Objek gambar yang ditangkap lensa kamera akan dipisahkan menjadi 3 warna primer yaitu merah (Red), hijau (Green) dan biru (Blue). Hasil tersebut akan dipancarkan oleh pemancar TV(Transmitter) berupa sinyal cromynance, sinyal luminance dan syncronisasi.

Selain gambar, pemancar televisi juga membawa sinyal suara yang ditransmisikan bersama sinyal gambar. Gambar dipancarkan dengan system amplitudo modulasi (AM), sedangkan suara dengan system frekuensi modulasi (FM). Kedua system ini digunakan untuk menghindari derau (noise) dan interferensi.

Gambar 3. Distribusi Objek Ke Televisi


2. SALURAN DAN STANDAR PEMANCAR TV
Kelompok frekuensi yang ditetapkan untuk transmisi sinyal disebut saluran (channel). Masing-masing mempunyai sebuah saluran 6 MHz dalam salah satu bidang frekuensi (band) yang dialokasikan untuk penyiaran TV komersial yaitu:
a) VHF bidang frekuensi rendah saluran 2 sampai 6 (54 – 88 MHz).
b) VHF bidang frekuensi tinggi saluran 7 sampai 13 (174 – 216 MHz).
c) UHF saluran 14 sampai 83 (470 – 890 MHz)

Ada 3 sistem pemancar TV yaitu sebagai berikut:
a) National Television System Committee (NTSC) digunakan USA
b) Phases Alternating Line (PAL) digunakan Inggris
c) Sequential Couleur a’Memorie (SECAM) digunakan Prancis

Sedangkan Indonesia sendiri menggunakan system PAL B. Hal yang membedakan system tersebut adalah format gambar, jarak frekuensi pembawa gambar dan pembawa suara.


3. PRINSIP KERJA PENERIMA TV

Gambar 4. Blok Rangkaian TV


Model dan jenisnya blok rangkaian TV bermacam-macam, tergantung pada merek TV yang digunakan.
Secara garis besar blok tersebut memiliki fungsi-fungsi sebagai berikut:
a) Antena Televisi
Antena TV menangkap sinyal-sinyal RF dari pemancar televisi. Antena diklasifikasikan berdasarkan konstruksinya ada 3 yaitu:
1) Antena Yagi
2) Antena Perioda Logaritmis
3) Antena Lup

Klasifikasi lain berdasarkan jalur frekuensi gelombang yang diterima adalah:
1) Kanal VHF Rendah
2) Kanal VHF Tinggi
3) Kanal UHF

(a)Antena VHF Rendah (b) Antena VHF Tinggi (c) Antena UHF

Gambar 5. Antena Yagi

Gambar 6. Antena Perioda Logaritmis Gambar 7. Antena Lup (Loop)


b) Rangkaian Penala (Tuner)
Rangkaian ini terdiri dari penguat frekuensi tinggi (penguat HF), pencampur (Mixer) dan osilator local. Rangkaian penala berfungsi untuk menerima sinyal TV yang masuk dan mengubahnya menjadi sinyal frekuensi IF

Gambar 8. Tuner

c) Rangkaian Penguat IF (Intermediate Frequency)
Rangkaian ini berfungsi sebagai penguat sinyal hingga 1000 kali. Sinyal ouput yang dihasilkan penala (Tuner) merupakan sinyal yang lemah dan sangat tergantung pada jarak pemancar, posisi penerima dan bentangan alam. Lingkaran merah menunjukkan rangkaian IF yang sebagian berada didalam tuner.







Gambar 9. Penguat IF

d) Rangkaian Detektor Video
Berfungsi sebagai pendeteksi sinyal video komposit yang keluar dari penguat IF gambar. Selain itu juga berfungsi untuk meredam sinyal suara yang akan mengakibatkan buruknya kualitas gambar

e) Rangkaian Penguat Video
Rangkaian ini berfungsi sebagai penguat sinyal luminan yangberasal dari detector video sehingga dapat menjalankan tabung gambar atau CRT (Catode Ray Tube)

f) Rangkaian AGC (Automatic Gain Control)
Rangkaian AGC berfungsi menstabilkan sendiri input sinyal televisi yang berubah-ubah sehingga output yang dihasilkan menjadi konstan. Lingkaran merah menunjukkan komponen AGC yang berada didalam sebagian IC dan sebagian tuner


Gambar 10. Rangkaian AGC

g) Rangkaian Penstabil Penerima Gelombang TV.
Rangkaian penstabil penerima gelombang TV diantaranya adalah AGC dan AFT. Automatic Fine Tuning berfungsi mengatur frekuensi pembawa gambar dari penguat IF secara otomatis

h) Rangkaian Defleksi Sinkronisasi
Rangkaian ini terdiri dari empat blok yaitu: rangkaian sinkronisasi, rangkaian defleksi vertical, rangkaian defleksi horizontal dan rangkaian pembangkit tegangan tinggi.

Gambar 11. Rangkaian Defleksi Vertical

Gambar 12. Rangkaian Defleksi Horizontal

i) Rangkaian Suara
Suara yang kita dengar adalah hasil kerja dari rangkaian ini, sinyal pembawa IF suara akan dideteksi oleh modulator frekuensi (FM). Sebelumnya, sinyal ini dipisahkan dari sinyal pembawa gambar

Gambar 13. Rangkaian Suara

j) Rangkaian Catu Daya (Power Supply)
Berfungsi untuk mengubah arus AC menjadi DC yang selanjutnya didistribusikan ke seluruh rangkaian.
Pada gambar, rangkaian catu daya dibatasi oler

Avenged Sevenfold - Nightmare

Nightmare
(Now your nightmare comes to life)

Dragged you down below
Down to the devil’s show
To be his guest forever
(Peace of mind is less than never)
Hate to twist your mind
But God ain’t on your side
An old acquaintance severed
(Burn the world your last endeavor)

Flesh is burning, you can smell it in the air
'Cause men like you have such an easy soul to steal (steal)
So stand in line while they ink numbers in your head
You’re now a slave until the end of time here
Nothing stops the madness turning, haunting, yearning, pull the trigger

You should have known
The price of evil
And it hurts to know that you belong here, yeah
Ooooh
It’s your fuckin’ nightmare
(While your nightmare comes to life)

Can’t wake up in sweat
'Cause it ain’t over yet
Still dancin' with your demons
(Victim of your own creation)
Beyond the will to fight
Where all that’s wrong is right
Where hate don’t need a reason
(Loathing self-assassination)

You’ve been lied to just to rape you of your sight
And now they have the nerve to tell you how to feel (feel)
So sedated as they medicate your brain
And while you slowly go insane they tell ya
"Given with the best intentions,
Help you with your complications"

You should have known
The price of evil
And it hurts to know that you belong here, yeah
No one to call
Everybody to fear
Your tragic fate is looking so clear, yeah
Ooooh
It’s your fuckin’ nightmare
Hahahaha

(Hahahahahahahahahahahahaha)

Fight (fight)
Not to fail (fail)
Not to fall (fall)
Or you’ll end up like the others
http://www.elyricsworld.com/nightmare_lyrics_avenged_sevenfold.html
Die (die)
Die again (die)
Drenched in sin (sin)
With no respect for another

Oh

Down (down)
Feel the fire (fire)
Feel the hate (hate)
Your pain is what we desire
Lost (lost)
Hit the wall (wall)
Watch you crawl (crawl)
Such a replaceable liar

And I know you hear their voices
(Calling from above)
And I know they may seem real
(These signals of love)
But our life’s made up of choices
(Some without appeal)
They took for granted your soul
And it’s ours now to steal
(As your nightmare comes to life)

You should have known
The price of evil
And it hurts to know that you belong here, yeah
No one to call
Everybody to fear
Your tragic fate is looking so clear, yeah
Ooooh
It’s your fuckin’ nightmare

Avenged Sevenfold - Buried Alive

Am C
Take the time just to listen
F E
When the voices screaming are much too loud
Am C
Take a look in the distance
F E
Try and see it all

Am C
Chances are that you might find
F E
That we share a common discomfort now
Am C
I feel I'm walking a fine line
F E
Tell me only if it's real

Dm C G
Still I'm on my way
G
(On and on it goes)
Dm C G E
Vacant hope to take

Am
Hey!
E F E F G
I can't live in here for another day
Am E F E
Darkness has kept the light concealed
F E G F
Grim as ever
Am E F E F G
Hold on to faith as I dig another grave
Am E F E
Meanwhile the mice endure the wheel
E
Real as ever
E Am
And it seems I've been buried alive!

C F E

Am C
I walk the fields through the fire

F E Am
Taking steps until I found solid ground
C
Followed dreams, reaching higher
F E
Couldn't survive the fall

Am C
Much has changed since the last time
F E Am
And I feel a little less certain now
C
You know I jumped at the first sign
F E
Tell me only if it's real


Dm C G
Memories seem to fade
G
(On and on it goes)
Dm C G E
Wash my view away


Am
Hey!
E F E F G
I can't live in here for another day
Am E F E
Darkness has kept the light concealed
F E G F
Grim as ever
Am E F E F G
Hold on to faith as I dig another grave
Am E F E
Meanwhile the mice endure the wheel
F E G F E
Real as ever
F E G F
And I'm chained like a slave
E
Trapped in the dark
E
Slammed all the locks
E
Death calls my name
F E G F
And it seems I've been buried alive!

Am C Dm G
Am C Dm F E G F
Am C Dm G
Am C Dm F E G F

Am F
Am F
Am F
Am F
Am Abm G F# F

E x7
E G F# F E

E
Take you down now
E
Burn it all out
E
Throw you all around
E G F# F
Get your fuckin' HANDS OFF ME!

E
What's it feel like?
E
Took the wrong route
E
Watch it fall apart
E G F# F E
Now you're knockin' AT THE WRONG GATE!

Ab Am B
For you to pay the toll
Am B C
A price for you alone
Ab Am B
The only deal you'll find
Am B C
I'll gladly take your soul

E
While it seems sick
E
Sober up quick
E E
Psycho lunatic crushing you with
G F# F
HANDS OF FATE!

E
Shame to find out
E
When it's too late
E
But you're all the same
E G F# F E
Trapped inside INFERNO AWAITS!

Ab Am B
Evil thoughts can hide
Am B B
I'll help release the mind
Ab Am B
I'll peel away the skin
Am B C
Release the dark within

E G F# G E
This is now your life
E G F# G E
Strike you from the light
E G F# G E
This is now your life
E G F# G E
Die, buried alive

Avenged Sevenfold - So Far Away

Em
Never been for anything
Em
Never chained but never free
G D
I lied to heal the broken love
Bm C
With all that it could

Em
Live the life so endlessly
Em
Saw beyond what others see
G D
I tried to heal your broken heart
Bm C
With all that I could

C
Will you stay
D
Will you stay away forever?

Em G
How do I live without the ones I love?
Am Em D
Time still turns the pages of the book, it's burnt
Em G
Facing times always on my mind
Am C D
I have so much to say but you're so far away

Em
Means a war of futures hold
Em
Foolish lies of grown and old
G D
And seems we're so invincible
Bm C
The truth is so cold

Em
A final song, a last request
Em
A perfect chapter laid to rest
G D
Now and then I try to find
Bm C
The place in my mind

C
Where you can stay?
D
You can stay awake forever!

Em G
How do I live without the ones I love?
Am Em D
Time still turns the pages of the book, it's burnt
Em G
Facing times always on my mind
Am C D
I have so much to say but you're so far away

E
Sleep tight
C
I'm not on pray
Am Em
The ones that we love are here with me
E
Lay away
C
A place for me
D
'Cause as soon as I'm done
C
I'll be on my way
D
To live eternally

(solo) E C Am Em
E C D C D

Em G
How do I live without the ones I love?
Am Em D
Time still turns the pages of the book, it's burnt
Em G
Facing times always on my mind
Am
And the light you let remains
C D
But it so hard to stay
Am C D Em
And I have so much to say and you're so far away

(solo- 3:30 2x) Em D Am G D/F# Em D C

(solo) Em D Am G D/F# Em D C (2x)
Em D C

Em
I love you
D
You were ready
Am G D/F# Em D C
The pain stroke in dark spines
Em
But I see you
D
An it lets me
Am G D/F# Em D C
Your pain is gone on hands of time

Em D C Em D C
So far away (And I need you to know)
Em D C Em D C
So far away (And I need you to need you to know)

Avenged Sevenfold - Victim

Standard tuning

I think it's pretty much right, let me know of any mistakes!

Intro:
Cm
Eb, Cm X2
Cm

C Fm
House full of roses, a letter on the stairs
C Fm
A tape full of messages for anyone who cares
Bb Ab
Collage of broken words, and stories full of tears,
Bb Ab
Remembering your life, 'cause we wish that you were here
C Fm
Nothing is harder than to wake up all alone,
C Fm
Realize it's not OK, it's the end of all you've known
Bb Ab
Time keeps passing by, but it seems I'm frozen still,
Bb Ab
Scars are left behind, but some too deep to feel

Cm
And some say this can't be real,
Fm Bb
And I've lost my power to feel tonight
Eb G
We're all just victims of a crime
Cm
When all's gone and can't be regained,
Fm Bb
We can't seem to shelter the pain inside
Eb G Cm
We're all just victims of a crime

C Fm
Some days you'll find me in a place I like to go,
C Fm
Ask questions to myself 'bout the things I'll never know
Bb Ab
What's left to find? 'Cause I need a little more
Bb Ab
I need a little time, can we even up the score?

Cm
Some say this can't be real,
Fm Bb
And I've lost my power to feel tonight
Eb G
We're all just victims of a crime
Cm
When all's gone and can't be regained,
Fm Bb
We can't seem to shelter the pain inside
Eb G
We're all just victims of a crime

(1st solo)

Cm Fm Eb
Nothing lasts forever, for all good things it's true
G Cm
I'd rather trade it all, while somehow saving you
Fm Eb
It must have been the season that threw us out of line
G Eb
Once I stood so tall, now I'm searching for a sign

Bb Cm
So don't need your salvation with promises unkind
Fm Eb
And all the speculation, save it for another time
Bb Cm Fm
'Cause we all need a reason, a reason just to stay, and some just can't be bothered
Cm
To stick around another day

(2nd solo)

Cm
Some say this can't be real,
Fm Bb
And I've lost my power to feel tonight
Eb G
We've all been victims of a crime
Cm
When all is gone and can't be regained,
Fm Bb
We can't seem to shelter the pain inside
Eb G
We've all been victims of a crime

Eb G
Victims of a crime
Eb G
Living with this crime

Cm
I'm missing you X4

Eb, Cm, Eb, Cm, Eb, Cm, Bb, Cm (or something)


R.I.P. James Owen Sullivan.