Key switch: reset ＊ 1, doorbell button ＊ 1. Microphone: full duplex, sensitivity: ≥ - 38 ± 3dBm. Antenna: 3DBI 1433 Ant 1. Speaker: built-in 8 Ω/1W. Wireless 433 transmission module: wake up the indoor Dingdong machine.
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