| Kenmeans,
Thanks. I design telephones for PSTN. I got a question posted to me to make a phone that message waiting lamp works in various pabx's.
The specs given is as follow:
Nortel - Logic on the message waiting line card interrupts the -150 V dc signal at 1 Hz intervals to provide a flashing message waiting light.
NEC - - 80Vdc steady or 60 IPM flashing
Avaya - -48Vdc (standard) or -85~165Vdc (with optional hardware) at 500ms On and 500ms Off repeated.
Alcatel - 10V rms connected by pulse ton = 60ms typique max =80ms and it is possible to apply 60v rms with the same typical time
That's all I have to work on now. I have no clue on what all those sentences means. Need to translate that to technical and waveform examples.
Thanks for helping out. |