🚀 go-pugleaf

DO NOT BUILD THIS!
	I built one of these devices a couple years ago.  It
	consisted of a voltage  divider tap to the base of a
	2n2222 whose collector tickled another 2n2222 buffer
	to an led.  In the on hook mode it would always draw
	a few uA but in off hook mode it would steal a
	couple milliamps to run the led.

	Anyway I used it successfully for two years in one
	appartment, but after short time in my new appartment a
	GTE guy came to look for the current loss.  They
	apparently sweep the voltage to measure the
	impedance of the line to check for faults.
	I guess that explains why I would see the light come
	on for no apparent reason during my night owl study
	times.

	The tech guy told me that they complain if there
	is more than 700kohm load on the line.

	I was trying to do this without batteries but I
	guess the only answer is to build a battery powered
	1Meg input impedance comparator circuit to detect less
	than 12Volts.  Just don't use the telco's power to run
	your circuit, and make sure you keep in mind  the
	voltages of the ring and onhook.

eddie < efrie@eecs.wsu.edu >


      ______/   ___/       ___/         /    ______/
     /         /   _/     /   _/       /    /        
    ____/     /     _/   /     _/     /    ____/ 
   /         /      _/  /      _/    /    /       
  _______/   ______     ______     _/    _______/