webster@romulus.rutgers.edu (John Clayton Webster) (09/24/90)
An odd thought sprang upon me recently while talking to a friend. Do telephones actually use sixteen tones rather than just twelve normally available? I apologise if this has been brought up before, I just found this group. Clay Webster [Moderator's Note: Actually, the topic has come up frequently. Yes, telephones have sixteen tone combinations available. The four you do not normally see on your dial are frequently known as A,B,C, and D. They have a very limited application at this time. Perhaps some readers will be so kind as to send you recent messages from the Digest discussing these tones and their application. PAT]
brent@uunet.uu.net (Brent Capps) (09/27/90)
> An odd thought sprang upon me recently while talking to a friend. Do > telephones actually use sixteen tones rather than just twelve normally > available? The extra tones are used in the AUTOVON/SCOPEDIAL system for precedence dialling. The only phone I've ever seen that uses them is a very peculiar device known as a "4-wire set". A 4W set is essentially a trunk-line combination that consists of a trunk with a special phone set terminating one end, and is used by the military to run direct connections from AUTOVON COs out to missle silos in the middle of God-knows-where. 4W sets use all 16 keys. The numeric keys and the * key are the same as on a 2500 set, but the # key is called A, and the right-hand row of keys are called (top to bottom) FO, F, I, and P. These keys are used for precedence dialling: A stands for Automatic (lowest), P for Priority, I for Immediate, F for Flash, and FO for Flash Override (the highest precedence level). The highest allowed precedence level associated with a particular set is datafilled at the CO; there are only a handful of FO 4W sets in the country. 4W sets are extremely strange beasts; their charms include off-hook ringing (the phone can physically ring while you are off-hook talking to someone else). This can be somewhat disconcerting to the uninitiated. 4W sets are a pain to design CO software for, mainly because of their hybrid nature (ever try to apply staggered dialtone to a trunk? It's not easy) and since there is little that a 4W set can do that a normal 2W set cannot, the CO mfgs have been pushing the military to phase them out. Brent Capps
cloutier@uunet.uu.net (Mark Cloutier) (09/27/90)
In article <12659@accuvax.nwu.edu> kentrox!ktxc5!brent@uunet.uu.net (Brent Capps) writes: >> An odd thought sprang upon me recently while talking to a friend. Do >> telephones actually use sixteen tones rather than just twelve normally >> available? These 4*4 phones are more popular in Europe, the application I heard of was to use the extra four keys as speed dial keys. This was in a PBX environment.
bill@toto.info.com (Bill Cerny) (09/28/90)
In article kentrox!ktxc5!brent@uunet.uu.net (Brent Capps) writes: >and since there is little that a 4W set can do that a normal >2W set cannot, the CO mfgs have been pushing the military to phase >them out. The base operator also has plug access to AUTOVON (now DSN?) trunks grouped by precedence. If you tire of reaching reorder when dialing '8' for routine AUTOVON, you call the operator and provide the authorization code for the precedence (P, I, F) and destination (CONUS, Overseas), to which she usually replies, "I'm sorry sir, there are no circuits available at this time." :-( In San Diego, things are a little better now. The old 1ESS AUTOVON switch is now a 5ESS, and all the Navy base step switches have been replaced by AT&T Sys 75 and 85 PBX's (are any slated for upgrade to Definity Generic 1 or 2?). Apparently, the 4-wire desk sets have been replaced by regular 2500 (or 74xx, or STU III) sets. You select AUTOVON precedence with the trunk code (80 for routine, 81 for priority); provided your station has the class of service mark to access that precedence (otherwise it's back to authorization codes and the operator). I accessed a routine AUTOVON trunk from a peon station, and pressed 'P', to which the AUTOVON switch announced "You may not access that precedence..." The AT&T PBX provides the proper ringing for incoming AUTOVON calls: routine precedence gives the normal double ring for "outside call", while priority (and above) gives a triple ring for "priority call." Bill Cerny bill@toto.info.com | attmail: !denwa!bill