PA> Bias Is an ac sig about 160khz used to erase the tape
PA> b-4 recording,and while recording,i.e. aprox 10-40 volts
PA> applied to erase head,simultan about 10 volts to 20 applied
PA> to record head,level of bias to rec head shifts freq responce
PA> of rec sig.
PA> i.e. more bias =less hf recorded on tape.
Is that a standard frequency for cassette and open reel decks today? 
Is less bias current applied to the record head, as well as possibly
1/4 to 1/2 the erase head voltage?  I once read that freq.  higher than
125khz might not gain much in the nineteen eighties, but maybe tape
improvements make it desirable now.  
PA> I am a master tech,tought by a TEAC JAP ENG.
Congratulations. 
I wonder, do you see much Tascam equipment?  Have you seen DVD players?  
...
 * ATP/qwk 1.42 * What grammar is to speech, logic is to reason.
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 * KMail 3.10m  1996:  The year of the BBS!
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