In the US, when I dial an inactive phone number, get a loud three tone sequence followed by an announcement that "this number is not in service". The tones do not seem to match the touch-tone frequencies.
I want to try using those tones to discourage the constant barrage of scam callers. Maybe if their computer gets that message they will take me off the list. At least is seems like it is worth trying.
So does anybody know what those tone frequencies are? If I create a circuit to generate that sequence I will share it with everybody.
I want to try using those tones to discourage the constant barrage of scam callers. Maybe if their computer gets that message they will take me off the list. At least is seems like it is worth trying.
So does anybody know what those tone frequencies are? If I create a circuit to generate that sequence I will share it with everybody.