physics a lvl studnts attention!!

[princessV]

hey anybody out dere can u tell me where can i get the proper PSTN resources for physics a lvls paper4.. plzz plzz plzz help me out guyz..

 

[Zishi]

Please do make topics in the right section. . .

-Topic Moved-

 

[Jazib]

PSTN is very well explained in the application booklet issued by cambridge!

 

[gerrard]

only use the cambridge booklet ..

and if you are in lhr go to wise college get sulehris application book it contains old apps questions with marking schemes

 

[Jazib]

sulehri's app questions are also nicely compiled. but never attemted any
cuz vo acdmy mein he karwa deta tha

 

[anzaar]

at Lahore Sir Iqbal is an A* teacher for physics O/A Level.

 

[princessV]

im frm BD.. can i find the booklet in british council??

 

[PlanetMaster]

The Public Switched Telephone Network, or PSTN, is the worldwide network of lines used to carry telephone calls. It is a "switched" network because a connection is made between caller and receiver before any communication begins. Originally, a physical circuit (formed via a number of switches) had to be formed between the caller and receiver, limiting the capacity of the network. This problem was resolved with the development of time division multiplexing.

The first telephone exchanges (where the circuit switches were located) were operated manually by the telephone operator. This was a slow process. Over time, the human operators were replaced with electromechanical switches. These were in turn superseded by electronic switches.

The telephone network can be visualised as a "hub and spokes" arrangement. When the call is made, if it is local to the exchange, then the signal is carried along a spoke to the local exchange (i.e., the hub) then routed down another spoke to the receiver. If the call is a "trunk" call (i.e., not local to the exchange) then the local exchange routes the call to the trunk exchange for onward delivery to the exchange local to the receiver. For international calls, the local exchange will route to an international gateway.

 

[Jazib]

simpler way would be to download and print it.

 

[princessV]

@ planet master.. is this the sufficient info for exam or i need to brows for more??

 

[anzaar]

@ PrincessV
Here is the A Level Science Application : Support booklet for Physics
please download the attachment.

 

[PlanetMaster]

Thanks for the effort but its already available in download section since 13th Feb! -p

 

[anzaar]

Please see the attachment of application ALevel Booklet
as desired.

 

[princessV]

thanxx a lot guyz!! i got it