Tek-Tips is the largest IT community on the Internet today!
Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!
-
Congratulations gkittelson on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!
Ringing Voltage in the USA??
- Thread starter doktor
- Start date
- Thread starter
- #4
youcandoit
Technical User
20hz is correct
here is a nice site found via google.
here is a nice site found via google.
- Thread starter
- #7
20 Hz is the nromal default unless it is a party line.
May I ask why you need to know? If you are making soemthing intended to detect rigning you need to make sure to include a range of frequencies wider than simple +/- 1 Hz. This is an important area of compatibilitiy that many novice designers neglect to consider.
Similar issues arise when designing equipment to detect DP or DTMF dialing, you must support the full range stated in the standards.
Best of luck
May I ask why you need to know? If you are making soemthing intended to detect rigning you need to make sure to include a range of frequencies wider than simple +/- 1 Hz. This is an important area of compatibilitiy that many novice designers neglect to consider.
Similar issues arise when designing equipment to detect DP or DTMF dialing, you must support the full range stated in the standards.
Best of luck
- Thread starter
- #9
Hi ISDNman
No, I posed this question because of some friends brought an old swedish (Ericsson Ericofon)analogue phone to the USA, where it couldn't ring.
The "speech-way" (loudspeaker/microphone) worked allright.
It was working allright in Europe, but it couldn't ring in the US.
I have asked them for more details.
dotor
No, I posed this question because of some friends brought an old swedish (Ericsson Ericofon)analogue phone to the USA, where it couldn't ring.
The "speech-way" (loudspeaker/microphone) worked allright.
It was working allright in Europe, but it couldn't ring in the US.
I have asked them for more details.
dotor
strmwalker
Technical User
doktor...sounds crazy but tell your friend to reverse
tip and ring it might work for your ringing problem.
even analog phones not all but some are polarity
sensitive.hope this helps.
strmwalker
tip and ring it might work for your ringing problem.
even analog phones not all but some are polarity
sensitive.hope this helps.
strmwalker
- Thread starter
- #11
I remember the ERICOFON! I repaired some of those back in the 1970s. North Electric was the importer and sold them thru North Supply. There were both rotory dial and 'Key-Call'(DTMF) versions.
Some of them had three conductor line cords. The ringer circuit was connected across the Red and Yellow leads. This way it could be used on two-party lines as 'tip party' or 'ring party' to ground. If it was a one-party, then you connected the Yellow and Green leads together for bridged ringing.
You might check the wiring in the set also. The ringer may have been disconnected.
If I remember correctly the last version of the ERICOFON had a neon lamp in the upper portion of the set near the receiver element that glowed when the set rang. I may even have one of the old catalogue sheets buried in a file here.
For a historical note, this type of ringer circuit was refered to as a 'straight line ringer' and would respond to the frequency range of 16-2/3Hz to 30Hz. And most ring generators in the power plants of 1A1 and 1A2 KTS used 30Hz ring generators in the Bell System and Independants. The CO ringing frequency for the Bell System was almost always 20Hz. In the non-Bell areas they used harmonic and synchronic ringers for multi-party lines. In GT land we had harmonic ringing with frequncies of 16-2/3, 25, 33-1/3, 50, and 66-2/3 Hz. So with these frequencies you could have a five-party line. Each type of ringer was 'tuned' to respond to only that frequency.
Now everything is pretty much standardized on 20Hz @ 90 to 105AC.
Hope this helps!
....JIM....
Some of them had three conductor line cords. The ringer circuit was connected across the Red and Yellow leads. This way it could be used on two-party lines as 'tip party' or 'ring party' to ground. If it was a one-party, then you connected the Yellow and Green leads together for bridged ringing.
You might check the wiring in the set also. The ringer may have been disconnected.
If I remember correctly the last version of the ERICOFON had a neon lamp in the upper portion of the set near the receiver element that glowed when the set rang. I may even have one of the old catalogue sheets buried in a file here.
For a historical note, this type of ringer circuit was refered to as a 'straight line ringer' and would respond to the frequency range of 16-2/3Hz to 30Hz. And most ring generators in the power plants of 1A1 and 1A2 KTS used 30Hz ring generators in the Bell System and Independants. The CO ringing frequency for the Bell System was almost always 20Hz. In the non-Bell areas they used harmonic and synchronic ringers for multi-party lines. In GT land we had harmonic ringing with frequncies of 16-2/3, 25, 33-1/3, 50, and 66-2/3 Hz. So with these frequencies you could have a five-party line. Each type of ringer was 'tuned' to respond to only that frequency.
Now everything is pretty much standardized on 20Hz @ 90 to 105AC.
Hope this helps!
....JIM....
- Thread starter
- #13
Excellent point syquest. These 3 line cords are primarily for grounded ringer configuration. Theese were very common among indiependents prior to deregulation. The have the added benefit that the subscriber is aware if the protector gound is broken.
Regarding ring frequencies, the Swedend has two different standards. 25 Hz +/- 3 Hz and 50 Hz +/- 1Hz.
If your phone has a 50 Hz ringer then it is not goign to ring on USA 230 Hz. A 25 Hz ringer might be able to be adjusted to ring on 20 Hz.
Good luck
Regarding ring frequencies, the Swedend has two different standards. 25 Hz +/- 3 Hz and 50 Hz +/- 1Hz.
If your phone has a 50 Hz ringer then it is not goign to ring on USA 230 Hz. A 25 Hz ringer might be able to be adjusted to ring on 20 Hz.
Good luck
- Thread starter
- #15
Hi all contributors to this request.
I have passed the info on to the friend of mine.
(He has bought the Ericofon in the USA, and has taken it to Europe/Denmark).
He could see that the wiring inside the US-model was diffrent to one Ericofon bought here in Denmark.
If he fails getting the phone to ring, he will bring it to my office for further investigations.
So far, so good.
Thanks for your help in this case.
doktor
I have passed the info on to the friend of mine.
(He has bought the Ericofon in the USA, and has taken it to Europe/Denmark).
He could see that the wiring inside the US-model was diffrent to one Ericofon bought here in Denmark.
If he fails getting the phone to ring, he will bring it to my office for further investigations.
So far, so good.
Thanks for your help in this case.
doktor
90 volts 30 cycle, by fed standard, same as 20 mil line current and 48 volts -tip +ring.. all limits are plus or minus 10 percent. the only one you can push if it's low is the 90v and 20 mil. either of those minus 10 can cause problems with switch line recognition
john poole
bellsouth business
columbia,sc
john poole
bellsouth business
columbia,sc
I just googled "ericophone" to find a website I have bookmarked at home that has wiring diagrams, history, and parts for ericophones for sale. Couldn't find it... but Holy Crow! the prices these things are going for now! People are paying US$200-400 for these things (I paid $40 for the one on my desk - 1957 vintage North Electric).
I'll post that URL later if the site is still live.
jsaxe
"When the going gets weird, the weird turn pro."
Hunter S. Thompson (R.I.P. Doc)
I'll post that URL later if the site is still live.
jsaxe
"When the going gets weird, the weird turn pro."
Hunter S. Thompson (R.I.P. Doc)
it's
jsaxe
"When the going gets weird, the weird turn pro."
Hunter S. Thompson (R.I.P. Doc)
jsaxe
"When the going gets weird, the weird turn pro."
Hunter S. Thompson (R.I.P. Doc)
Yes, ISDNman, I believe cost was the main reason why most key system ring generators used 30Hz instead of 20Hz. I guess 2 toroids were cheaper than 3 toroids. I always thought the 20Hz ringing sounded much better than the 30Hz. If you had sharp hearing you could tell the difference on a key system between a line ringer and a common audible ringer by its frequency, and the interrupter timing was different on the KSU than on the CO ringing.
....JIM....
....JIM....
- Status
Similar threads
- Locked
- Question