HP Model 743 PC - Manual (Page 83)

4-9
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 ste-
reo 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 driv-
ing 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.