Yea simple.  put a bridge rect on the tip and ring lines.  Look up hte
stats on a telephone.  I beleive a ring is a 42V AC single and as for the
other when you pick up there is a DC current flow.  Just check for that.
Shouldnt be too hard to do with analog logic (not that i would ever try
w/o exploiting every possiblity for a digital solution first :)  AT&T
makes a nifty little plug that will cut off and answering machine when
the tele picks up.  Its not much bigger if at all then an splitter.  Go
buy one and bust the thing open.  reverse engineer it(dont tell
microsoft) and then you have your current checking bit...


later
        John
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John Johnson  Team OS/2 member     |Windows NT.  VMS with a GUI!
johnsonj@ccwf.cc.utexas.edu        |.386:windows synonym for "gadget"
johnsonj@utdallas.edu              |Windows 95 == CP/M 95
johnsonj@computek.net              |Windows 4.0 -> Windows 95 -> WinEver
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