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6 Introduction
1.3What is common interface?
Some broadcasts are scrambled so that only paid subscribers can enjoy them. Scrambled services can only be viewed with a Conditional Access Module (CAM) and a subscription card belong- ing with the scrambling system.
Common Interface (CI) is the slot on a digitial receiver into which a conditional access module may be insterted. The front of the digital receiver has two common interfaces.
To watch a pay service, you should take the following steps:
1.Purchase a conditional access module and a subscription card for the pay service you want to watch.
2.Insert the subscription card into the conditional access module.
3.Insert the conditional access module into a common in- terface on the front of the digital receiver.
To view the information about the module and subscription card inserted into the digital re- ceiver, select the Common Inter- face menu. You should see a screen like the left figure.