You can easily add 23 radio channels in your Airtel Digital TV STB if you are aligned to SES 7.

The steps for adding radio channels are following

1. Press "menu" button on your ADTV Remote.

2. Go To my settings -> system setup -> free to air channels -> Find Channels

3. Enter following values using your ADTV remote in the FTA SETTINGS FOR SEARCH screen

Satellite: Insat -4a (actually any)
Search Mode: FTA + CAS
Transponder: User
Frequency: 11600
Polarisation: Horizontal
Symbol Rate: 28800
FEC: 5/6

4. Now press Blue button on your ADTV remote.

5. You will find 33 TV Services and 23 Radio Services on the screen.

6. Press Blue button on your ADTV remote to store them in your STB.

7. Press exit button on your ADTV remote to come back to current TV channel.

The stored radio channels can be listen on channel numbers starting from 733.
Or you can find them after channel number 999 by their name (B1, B2, B3 .... B23).
A screensaver will display on your screen while listening to these radio channels. The screensaver displays a slow bouncing message "The best music only on Airtel".

The 23 radio channels are named from B1 to B23. All the radio channels are National and Regional radio channels of All India Radio (AIR) including MW & FM channels. These are the same 23 radio channels available on DD Direct Plus DTH service.

ADTV customer support officially denies about any radio service available from their side.