The connector to use with the 500 series PowerBooks is a standard 3.5mm stereo plug.
A stereo plug has three sections on it, the tip, the ring and the sleeve. Each of these sections of the plug are separated by a black band, a stereo jack would have two black bands, a mono jack would have only one black band.
It is not necessary to use the RCA phono to 3.5mm jack adapter that were used by some previous Macintosh models. These adapters had built in attenuation that would drop the signal level for the sound input on certain Macintosh computers.
Article Change History:
04 Apr 1995 - Corrected size of phono plug.
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