Seems that I4m going to use this solution, just wait for 15-20 sec and then
start with the time calculation, since there is no 15 khz billing tone :-(
Javier
PD To isolate I4m going to use a 600 ohm trafo, 4 caps and 1.5 microH coils
!!??


>>Gotta agree with this one. Assuming he doesn't listen to the dialtone as a
>>hobby, you're mesurements might be 5 minutes higher or something... so as
>>long as the telco's are less....
>
>I'd guess about 15 sec per call.