Radio, Stereo, and Compact Disc: Description and Operation

System Diagram

System Diagram:

SYSTEM DESCRIPTION

1. CD (Compact Disc) player outline
a. A compact disc player uses a laser pickup to read digital signals recorded on a compact disc (CD). By converting the digital signals to analog, it can play music and other things. In general, CD players can play 4.7-inch (12 cm) and 3.2-inch (8 cm) discs.

HINT:
- Do not disassemble any part of the CD player.
- Do not apply oil to the CD player.
- Do not insert anything but a CD into the CD player.

CAUTION: Do not look directly at the laser pickup because the CD player uses an invisible laser beam. Be sure to only operate the player as instructed.




2. AVC-LAN Description

a. What is AVC-LAN?
AVC-LAN, an abbreviation for "Audio Visual Communication Local Area Network", is a unified standard developed by the manufacturers in affiliation with Toyota Motor Corporation. This standard pertains to audio and visual signals as well as switch and communication signals.

b. Purpose:
Recently, car audio systems have rapidly developed and the functions have vastly changed. The conventional car audio system is being integrated with multi-media interfaces similar to those in navigation systems. At the same time, customers are demanding higher quality from their audio systems. This is merely an overview of the standardization background. The specific purposes are as follows.

1. To solve sound problems, etc. caused by using components of different manufacturers through signal standardization.
2. To allow each manufacturer to concentrate on developing products they do best. From this, reasonably priced products can be produced.

HINT:
- If a short to +B or short to ground is detected in the AVC-LAN circuit, communication is interrupted and the audio system will stop functioning.
- The radio receiver assembly provides resistance to make communication possible.
- The car audio system with an AVC-LAN circuit has a diagnostic function.
- Each component has a specified number (3-digit) called a physical address. Each function has a number (2-digit) called a logical address.

3. Communication system outline
a. Components of the audio system communicate with each other via the AVC-LAN.
b. The master component of the AVC-LAN is a radio receiver assembly with a 60 to 80 Ohms resistor. This is essential for communication.
c. If a short circuit or open circuit occurs in the AVC-LAN circuit, communication is interrupted and the audio system will stop functioning.

4. Diagnostic function outline
a. The audio system has a diagnostic function (the result is indicated on the master unit).
b. A 3-digit hexadecimal component code (physical address) is allocated to each component on the AVC-LAN. Using this code, the component in the diagnostic function can be displayed.