hb9zz@bernina.ethz.ch (Marco Zollinger) (01/09/91)
I'm devlopping a little databank program for the atari st and need the frequecy of the dial tones and eventually the waveform. Thanks to anybody helping me Ciao --- Rick
jon_sree@world.std.com (Jon Sreekanth) (01/10/91)
In article <1991Jan9.102713.10815@bernina.ethz.ch> hb9zz@bernina.ethz.ch (Marco Zollinger) writes:
I'm devlopping a little databank program for the atari st and need the frequecy
of the dial tones and eventually the waveform.
Dial tone is 350Hz and 440Hz sine waves together, at equal amplitudes
(This is the so-called precise dial tone. If you're generating a dial
tone, this is the way to do it. Many chips that detect dial tone simply
look for energy in a broad band of frequencies : for example, the
Sierra Semi 2400 baud modem looks in 300 - 660 Hz, center 480 Hz)
Regards,
/ Jon Sreekanth
Assabet Valley Microsystems Fax and PC products
346 Lincoln St #722, Marlboro, MA 01752 508-562-0722
jon_sree@world.std.comtomb@hplsla.HP.COM (Tom Bruhns) (01/11/91)
hb9zz@bernina.ethz.ch (Marco Zollinger) writes: >I'm devlopping a little databank program for the atari st and need the frequecy >of the dial tones and eventually the waveform. There'll probably be lots of replies, but: | 1209 | 1336 | 1477 | 1633 | where the integers are the ------------------------------------- frequencies in Hertz. 697 | "1" | "2" | "3" | "A" | Normally one of the two ------------------------------------- (the high tone? from my 770 | "4" | "5" | "6" | "B" | poor memory) is a bit ------------------------------------- "hotter" than the other, 852 | "7" | "8" | "9" | "C" | by perhaps a dB. I'm ------------------------------------- sure someone will set us 941 | "*" | "0" | "#" | "D" | straight on this if it's ------------------------------------- wrong ;-)
tad@ssc.UUCP (Tad Cook) (01/14/91)
In article <1991Jan9.102713.10815@bernina.ethz.ch>, hb9zz@bernina.ethz.ch (Marco Zollinger) writes: > I'm devlopping a little databank program for the atari st and need the frequecy > of the dial tones and eventually the waveform. > Standard dialtone in North America is 350 plus 440 Hz. You didn't want the frequencies for standard Dual Tone Multifrequency tone dials, did you? Here is the scheme: 1209hz 1336hz 1477hz 697hz 1 2 3 770hz 4 5 6 852hz 7 8 9 941hz * 0 # When dialing a digit one, you get 1209+697 hz. A digit will put out the tones for the row and column that it is in. There is also a fourth column at 1633 hz available, but I am assuming that this is not for military autovon networks! Levels should be about -9 to -6dbm (275 to 388 mv) across the line, with about the levels about the same, or the high frequency a db or two hotter. Tad Cook Seattle, WA Packet: KT7H @ N7HFZ.WA.USA.NA Phone: 206/527-4089 MCI Mail: 3288544 Telex: 6503288544 MCI UW USENET:...uw-beaver!sumax!amc-gw!ssc!tad or, tad@ssc.UUCP