| Standard Tones | ||||
|---|---|---|---|---|
| 1209 Hz | 1336 Hz | 1477 Hz | 1633 Hz | |
| 697 Hz | 1 | 2 | 3 | A/FO |
| 770 Hz | 4 | 5 | 6 | B/F |
| 852 Hz | 7 | 8 | 9 | C/I |
| 941 Hz | * | 0 | # | D/P |
| Special Tones | |||||
|---|---|---|---|---|---|
| 620 Hz | 440 Hz | 425 Hz | 400 Hz | ---- | |
| 480 Hz | Busy US | Ring-Back US | High tone | ||
| 450 Hz | Ring-Back UK/Ireland | ||||
| 350 Hz | Dial Tone US/UK | ||||
| ---- | Busy/Dial/Ring-Back Europe* | Busy UK | |||
Obsolete from here onwards
| "Phreaking Boxes" |
|---|
| Blue |
| Red |
| "Green Box" | ||
|---|---|---|
| 2600 Hz | 900 Hz + 1500 Hz | |
| Coin Collect | ||
| Coin Return | ||
| Ringback | ||
| Operator MF Frequencies | ||
|---|---|---|
| 1 | 2 | 3 |
| 4 | 5 | 6 |
| 7 | 8 | 9 |
| 0/10 | 11/ST3 | 12/ST2 |
| KP | KP2 | ST |
*Ireland does not use this as the Ring-Back tone, the UK doesn't use this tone at all.