@dopefish You're right. It looks like that checkbox doesn't appear on the N66U for EU routers (which possibly explains why I didn't remember it). I think that's because it wasn't part of the original code base and is only enabled by manually setting that NVRAM variable.
Code:
if(country == "EU"){ //display checkbox of DFS channel under 5GHz
if(based_modelid == "RT-AC68U" || based_modelid == "RT-AC68U_V2" || based_modelid == "DSL-AC68U" || based_modelid == "RT-AC69U"
|| based_modelid == "RT-AC87U"){
if(document.form.wl_channel.value == '0' && '<% nvram_get("wl_unit"); %>' == '1')
$('dfs_checkbox').style.display = "";
}
}
It
was added into the later firmwares which is why it appears in Merlin's.
Code:
else if(country == "EU"){ //display checkbox of DFS channel under 5GHz
if(based_modelid == "RT-AC68U" || based_modelid == "RT-AC68A" || based_modelid == "4G-AC68U" || based_modelid == "DSL-AC68U"
|| based_modelid == "RT-AC87U"
|| based_modelid == "RT-AC3200"
|| (based_modelid == "RT-AC66U" && wl1_dfs == "1") //0: A2 not support, 1: B0 support
|| based_modelid == "RT-N66U"){
if(document.form.wl_channel.value == '0' && wl_unit == '1'){
document.getElementById('dfs_checkbox').style.display = "";
check_DFS_support(document.form.acs_dfs_checkbox);
}
}
Personally I wouldn't use the Auto setting anyway. Just set it to something like channel 100 and see how it works out.