引自百度知道:
打开oppo A37m手机桌面,找到拨号键,点击进去
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进到拨号界面,输入代码 *#*#4636#*#*
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进到手机测试功能,点击手机信息,进去设置,看到很多功能,就往下拉,找到“设置首选网络类型”
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点击进入“设置首选网络类型”,进到里面设置3G模式,点击红色框框哪里的功能即可设置完成
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设置后,返回界面,就可以看到3G网络了,仔细 观察右上角3G网络,设置成功了,如果你需要4G网络的话,就继续进去设置成4G网络即可,红色框框哪里是4G/3G/2G网络
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如果,你想要2G,网络,就在拨号页面输入*#2323#,就会自动变成2G网络,不需要2G网络,就再输入一次*#2323#,即可关闭2G!
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