Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!pacbell.com!lll-winken!telecom-request From: wb8foz@mthvax.cs.miami.edu (David Lesher) Newsgroups: comp.dcom.telecom Subject: More Even More on Selective Ringing Message-ID: Date: 28 Mar 91 23:39:28 GMT Sender: Telecom@eecs.nwu.edu Reply-To: David Lesher Organization: NRK Clinic for habitual NetNews abusers Lines: 32 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 11, Issue 252, Message 7 of 11 {How did *I* get started on this? - I've NEVER had a party line.} Both Donald and Larry have brought up good points. First, my BSP 500-114-100 titled "Ringing Limitations" answers Donald's query. Paragraph 3.04 says {talking about eight party} Coded ringing is used to differentiate between stations.... In other words, it is only "semi-selective" ringing. While I have not dug too deeply into this aspect, one advantage of at least the two party Bell method was ANI. While the trick with the tapped ringer coil added some noise, it DID allow the CO to figure if Mr. Tip or Ms. Ring was calling Fargo without a "numberpleeze." The isolators, such as a 28A or a 425A, are gas tubes. They don't conduct until a LARGE (~90v) dc voltage is impressed on the line. Ringing is on top of that. Thus, during talking, no unbalance thru the ringer coil, and less noise. But, if you have a 28A or other of the myriad items Ma mentions (11A's, 687B's, 425&6A tubes, 426N diodes and D180036 isolators, to name a few) can you ALSO have ANI, and if so, HOW? Here's a mix of old and new: Can you have party line selective ringing on ESS's? wb8foz@mthvax.cs.miami.edu (305) 255-RTFM