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Functions of satellite TV and satellite

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Willen

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I don't have such satellite TV receiver yet but now a days, a tv programme transmitted from satellite can be pause and play at home. How it can be possible? What is the system? Please!
 
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They normally have a hard drive inside the receivers which buffers / stores the video stream.

There is also Video on Demand which streams the video signal via the internet - much like Youtube.
 
They normally have a hard drive
inside the receivers which buffers /
stores the video stream.
There is also Video on Demand which
streams the video signal via the
internet - much like Youtube.

It means, when we want to Pause or Record whole day's program, Should we have to keep ON the receiver, to record the program continuously transmitted from station? Can we able to copy and paste these recorded videos into PC?
 
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It means, when we want to Pause or Record whole day's program, Should we have to keep ON the receiver, to record the program continuously transmitted from station?
Yes - if you turn the power off then it won't be able to record. Most will come out of standby to record a program then go into standby when they are finished though.
Willen said:
Can we able to copy and paste these recorded videos into PC?
It depends on what recorder you have - do you have the make and model number ? Most with internal hard drives will not allow you to access the data on a PC. Some which are compatible with external hard drives may allow this function.
 
Hi again after 4 years(in the thread),
As I know the TV satellite station in space is placed in zero gravity and it's not running like GPS satellites run. Then when the earth goes away to round the sun then how it follows the earth? If the motion of the satellite has been set same as earth, then how they make it possible? It needs to round the earth in 24 hours and need to round the sun in 365 days same as earth? How they set the motion of the satellite?
 
Hi again after 4 years(in the thread),
As I know the TV satellite station in space is placed in zero gravity and it's not running like GPS satellites run. Then when the earth goes away to round the sun then how it follows the earth? If the motion of the satellite has been set same as earth, then how they make it possible? It needs to round the earth in 24 hours and need to round the sun in 365 days same as earth? How they set the motion of the satellite?

Simple answer - GRAVITY.
 
But why things float in space (lets say between the earth and the moon)?
 
Witten,

Standing still, swing an object (like a ball), that is attached to a string, around yourself. The ball is in an orbit around you, right?

It stays away form your body, rotating in a circle around you. Similar to the graphic below:
upload_2016-3-14_11-13-43.png

Or, with a satellite:
upload_2016-3-14_11-1-48.png


In this example, you are the Earth (the source of the gravity), the string is equivalent to gravity and the ball, which is moving in a circle and so has velocity, is the satellite.

This is also true on the Earth and the Moon, or the Sun and Earth or our Solar System and our galaxy!

The above are Non- synchronous examples.

Now, while swinging the ball, rotate your body as well, keeping your eyes on the ball - the ball is now in a synchronous orbit: you AND the ball are rotating at the same angular speed.

Was this helpful?

If so, we can move on to :zero-gravity" and the term "Float" in space.
 
How mathematical do you want to get?

The gravitational force of attraction between two objects is given by:

F = (G .m.M) / r^2

where G is the Gravity Constant (6.674 x 10^-11 N m^2 kg^-2)
m is the mass of the smaller body
M is the mass of the larger body
r is the distance between the centres of mass of the two bodies

The centrepetal force acting on a body in circular motion is given by:

F = (m.V^2)/r
where m is the mass of the body
V is the instantaneous velocity of the body
r is the radius of the circle

Putting these two equations together we end up with:

V^2 = G.M/r
G.M is a constant, mass of the earth times the gravity constant

Putting this into words, the lower the satellite orbit (r) the faster the satellite must move (V)
So for a geosynchronous orbit, the velocity must be such that the satellite completes the distance of its orbit in 24 hours.

So from all this, when you know the mass of the earth and the gravity constant, you can calculate how fast and at what height the satellite must move to stay in a fixed position in the sky.


As for a small object half way between the earth and the moon, the gravity force on it are very small, so it will not go far very quickly.
But, over time it will move, either it will drift off into space, or it will eventually fall to earth.


In this case, yes it is rocket science! :)

JimB
 
But why things float in space
The simple answer:
1) The earth pulls objects in. ( Gravity ) Just like you are pulled down right now. If you are far away from earth the pull is less.
2)Objects want to go in a straight line. It is hard to turn a corner. It is hard to go in a circle. Think about riding in a car, turn hard and the people (in the car) are pulled to the outside of the turn.
1+2) Earth pulls down. & Orbiting (going in a circle) pulls out. "float" is when ( pull down = pull out )
 
I can't remember exactly but doesn't a satellite travel at 17,000 miles per hour so that it stays over one spot on Earth as the Earth spins around each day? It is called a Geosynchronous Earth Orbit.
But some people still think the Earth is flat and stationary. They believe the heavens are spinning around us.
 
I can't remember exactly but doesn't a satellite travel at 17,000 miles per hour so that it stays over one spot on Earth as the Earth spins around each day? It is called a Geosynchronous Earth Orbit.
..............
Yes, the concept was first proposed by Arthur C. Clarke in 1945.
He was a true visionary science fiction writer and actually included some real science in his fiction.
 
But some people still think the Earth is flat and stationary. They believe the heavens are spinning around us.
I can not get the flat idea to work.
I have argued for the idea that the world is hallow and we line on the inside. The universe is in a time warp in the center. (I don't believe this like I don't believe in a 6000 year old world) It is an experiment in proving things that are wrong. lol
 
the simple answer is that the satellite falls towards the earth at the same velocity it is traveling away from it...and no air resistance to slow it down...
....my belief is that there is a lucky guy sitting in the middle who gets to push alot of buttons!

here's one,lol...
 
I know a satellite rotates (rotating satellite like some satellite phone stations) in its orbit due to centrifugal force and gravity of centre object. But how they pause a satellite (which do not rotates, like TV satellite) in zero gravity? How they take reference in space to lock the movement?
 
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