Review on SIM800C Wireless Quad Band Communication Transmission by Jyothish Pillai

I live in Milwaukee, not in a big city but surrounded by LTE towers. This thing is completely in the dark. No signal. AT+CSQ returns +CSQ: 0.0. A text document in Chinese was sent to me in response to my return request. This document shows the fact that only 2G networks are supported. "Connect the 2.4GHz GSM antenna to the module, insert a SIM card (Note: support Micro/Nano card, support 2G/3G/4G card from China Mobile or China Unicom -Mobile phone), but does not support 3G/4G network, does not support telecom card), plug it into the USB port of the computer, if you use it for the first time, you need to install the CH340 serial port driver. After starting the module, the indicator flashes once per second at first, and after the initialization time, the indicator flashes every 3 seconds and the module starts to work normally. Then you can control the SIM800C module with AT commands."and here" Sending English text messages (TEXT mode) Insert the SIM card, start the module and control the module, after the module is successfully registered that the module has been registered in a 2G network). "Unfortunately 2G networks q" In the US, major network operators are be in the process of retiring 2G service: AT&T stopped providing 2G networks in 2016. will launch its 2G CDMA network in late 2020. October 21, 2020 "In other words, this thing is a tiny boat anchor. Don't waste your time.