??? 07/13/05 14:03 Read: times |
#97217 - Correction Responding to: ???'s previous message |
Having last encountered this detail a decade or so ago, I took my own advice and looked in a textbook.
Apparently the "ring" tone is a 20 Hz sinusoid 253.8 volts p-p or 90 volts RMS centered about the "on-hook" voltage, which is the -48 volt battery potential. The peak voltage with respect to ground (0-volts) is +78.9. This information can be found on page 134 of Warren Hioki's book TELECOMMUNICATIONS, published by Prentice-Hall in 1990. RE |
Topic | Author | Date |
First:Wiring Error Detection! | 01/01/70 00:00 | |
It depends | 01/01/70 00:00 | |
First observation | 01/01/70 00:00 | |
First observation | 01/01/70 00:00 | |
Danger of surges | 01/01/70 00:00 | |
Sort of. | 01/01/70 00:00 | |
Sort of | 01/01/70 00:00 | |
Re: Sort of... | 01/01/70 00:00 | |
Phone line transients | 01/01/70 00:00 | |
Schematic of a simple filter | 01/01/70 00:00 | |
Research... | 01/01/70 00:00 | |
router | 01/01/70 00:00 | |
gas discharge tubes | 01/01/70 00:00 | |
GDT | 01/01/70 00:00 | |
Gas discharge tubes | 01/01/70 00:00 | |
Oh dear... | 01/01/70 00:00 | |
Gas Tubes | 01/01/70 00:00 | |
Or | 01/01/70 00:00 | |
Ring. | 01/01/70 00:00 | |
Where's Ring? | 01/01/70 00:00 | |
I say .. | 01/01/70 00:00 | |
Telephone systems | 01/01/70 00:00 | |
Telephone systems | 01/01/70 00:00 | |
tester | 01/01/70 00:00 | |
Yep Jan! | 01/01/70 00:00 | |
Even for testing not allowed | 01/01/70 00:00 | |
Line simulator | 01/01/70 00:00 | |
Another Misunderstanding Kai | 01/01/70 00:00 | |
misunderstanding | 01/01/70 00:00 | |
Jan | 01/01/70 00:00 | |
Confusion... | 01/01/70 00:00 | |
quote from my previous post | 01/01/70 00:00 | |
It's a current loop ... | 01/01/70 00:00 | |
Correction | 01/01/70 00:00 | |
ring? | 01/01/70 00:00 | |
Yes Jan! | 01/01/70 00:00 | |
Agreed | 01/01/70 00:00 | |
it explains a few things, though | 01/01/70 00:00 | |
Phone Line Ground | 01/01/70 00:00 | |
Not quite offtopic... | 01/01/70 00:00 | |
Alternative schematic | 01/01/70 00:00 | |
Just a simple comparsion !!!!!!!!!!!!!!! | 01/01/70 00:00 | |
please help me (telepone)![]() | 01/01/70 00:00 |