joseph@milton.u.washington.edu (Joseph Chan) (01/23/91)
I understand that the ring voltage is not internationally standardized. My specific question is that what is the phone line voltage provided by each Asia countries? (I am interested to find out the phone line voltage for Hong Kong and Indonesia). If I bring a phone/fax (based on CNG tone, I assume that there is no distinctive-ring service provided by any Asia country) to Indonesia or Hong Kong, will it work? (Of cause I would need a 220v power supply for this device) Thank you for any information. Please reply by e-mail to joseph@bofur.bioeng.washington.edu.
julian%bongo.UUCP@nosc.mil (Julian Macassey) (01/25/91)
In article <16306@accuvax.nwu.edu>, joseph@milton.u.washington.edu (Joseph Chan) writes: > I understand that the ring voltage is not internationally > standardized. The ringing voltage on telephone lines varies between 150 and 40 Volts. The voltage depends upon, the local standard ringing voltage at the CO, the length of the loop (phone line) between the CO and the subscriber, the current pulled by the ringer (called REN in the US) and lastly the number of ringers attached to the line. So, you can consider that the standard voltage is about 90-100 Volts. What does vary is the frequency of the voltage. In the the U.S. the frequency is usually 20 Hz, it can be other frequencies. In other parts it is often 50 Hz. So, briefly, a gong (bell) type ringer from the U.S. may not work in other countries because they are picky about the ringing frequency. Cheap and sleezy gong ringers will ring with any type of AC applied. Also "warble" ringers, the ones that sound like sick birds or crickets in heat are usually "FCC Type B" ringers and will respond to frequencies between 15 and 68 Hz - the truth is they will respond up to a 150Hz most of the time. So, a warble ringer should work anywhere. > My specific question is that what is the phone line > voltage provided by each Asia countries? (I am interested to find out > the phone line voltage for Hong Kong and Indonesia). I thought the specific question was ringing voltage, now it is line voltage. OK, I'll play along. Hong Kong is mostly UK gear so the line voltage will be around 50 - 52 Volts. I am not familiar with Indonesia, but you will find that the line voltage for most of the world is 48V, give or take a few. The exception being Western Germany which is 60V. Some parts of Italy used to be 60V too. The Phillipines have a ton of Seimens gear, so they may be 60V. But in short, assuming the dialing system of the phone/fax is compatible be it pulse or DTMF, and assuming the ringer is a class B, it will work anywhere in the world. Julian Macassey, n6are julian@bongo.info.com ucla-an!denwa!bongo!julian N6ARE@N6YN (Packet Radio) n6are.ampr.org [44.16.0.81] voice (213) 653-4495
rees@pisa.ifs.umich.edu (Jim Rees) (01/30/91)
In article <16379@accuvax.nwu.edu>, julian%bongo.UUCP@nosc.mil (Julian Macassey) writes: > I am not familiar with Indonesia, but you will find that the line > voltage for most of the world is 48V, give or take a few. Depends on where you are in Indonesia. I spent a week in Dabo Singkep once, and the ring voltage and frequency on the phone line depends on how fast you turn the crank. The loop talk current depends on how fresh the batteries are. I've been trying to call Dabo since I got back, and I can't convince the AT&T operator to stay on the line for the ten minutes or so that it takes the operator in Indonesia to get through. Seems to me that in the old days, the operator would take the number you wanted to call, then ring you back when she was able to get through. Is there some way to get them to do that today?