Connecting Cables

Audio Connection

Audio Connection

Model 743 Board Computers provide compact disc-quality audio input and output in stereo with a 16-bit coder-decoder (CODEC) over a frequency range of 25-20,000 Hz. Output is provided by a small internal speaker and a stereo headphone mini-plug (8 ohms impedance). Input is provided by a stereo line-in and mono microphone mini-plugs.

The CODEC combines CD quality stereo A/D converters for microphone and line input levels. D/A converters for driving headset and line outputs are used. The input sampling rate and format are programmable, as are the input gain control (used for software control of recording levels) and output atten- uation.

A 1/8-inch mini-jack is used for the speaker out connection. The other audio signals are on a 9-pin micro D-sub connector. The output is capable of driving 8 ohms; it can also be used for higher impedance devices with little or no additional distortion. A line-level input can be driven by the headset output.

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