The majority of smartphones and functions machine are DTMF code. Standby 11-13 MA, 1 relay open 44MA, 2 relays Open 77MA, 3 relays Open 110MA, 4 relays open 140MA, 5 relays open 170MA, 6 relays open 197MA, 7 relays open 223MA, 8 relays open 247MA.
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