Matt Ion,
  In a message on 20 March, you wrote to me :
(cut)
MI> sine signal, typically 40kHz-80kHz or higher, that boosts the signal on t
MI> tape to avoid "zero-crossing" distortion.  
Weren't tapes originally "biased" with a magnet, some way or other?  I don't
think it worked quite well.  
...
 * ATP/qwk 1.42 * The fewer our wants, the more we resemble the gods.
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