3 ms·
About 90 volts. (48v is the nominal on-hook voltage; Wikipedia tells me that the official ring voltage spec is 60 to 105 volts RMS at 20 HZ.) This page has a ci
by wolfgang42 5y ago
About 90 volts. (48v is the nominal on-hook voltage; Wikipedia tells me that the official ring voltage spec is 60 to 105 volts RMS at 20 HZ.) This page has a circuit for generating the appropriate signal given a 12 volt input: http://techlib.com/electronics/telephone.html http://techlib.com/electronics/telephone.html (plus a small extra circuit for using a lower voltage for control signals).