GL SFT1200 Opal can't find 5GHz wifi

Recently, I bought an SFT 1200 Opal to enhance the connectivity of some of my devices. It works perfectly when I connect it to the 5GHz Wi-Fi at home and use it as a repeater.

However, I'm encountering a problem when I try to connect it to the 5GHz Wi-Fi at my workplace. The SFT 1200 Opal can't even detect the 5GHz network, whereas my laptop connects to it without any issues.

How can I resolve this problem?

Your 5GHz work wifi might be using a DFS channel.

The 2.4GHz channel works I guess? (If there is one).

This thread GL-A1300 - How to disable DFS validation? might have some hints for you.

The post by @AnotherPhil has the answer.

The 2.4GHz works, it the only bandwidth which Opal connects to.

So I have to make some changes on the wifi basically?

Have a read of the thread I posted above.

Opal can't do 160 MHz for example.

So check the settings of your work wi-fi

Yes, but I didn't understand much.

I've set the 5GHz to 64 MHz, but still doesn't show.

64 MHz isn't a valid bandwidth.
There is 20, 40, 80 and 160 MHz.

It's not about the frequency, it's about the bandwidth of the 5 GHz channel.
On Windows, you can use a software like WifiInfoView to get all parameters.

Country code of your Wi-Fi is interesting as well.
As you can see there is DFS on nearly all 5 GHz channels.

Try to use a channel without DFS, like Channel 42

But setting it to 42MHz will the wifi lose some speed? Also but doing this my other devices can still detect the 5GHz right?

Setting it to Channel (!) (not MHz!) 42 will lose bandwidth which will cause lower speed - if currently is 160 MHz is used.

Ok if I set the channel to auto it should work? But this thing of different channel, DFS, ... Has impact only on routers or every devices? For example, my laptop with AX wifi card connects perfectly to the 5GHz with current settings.

It depends on the Wi-Fi hardware. Opal seems to not support DFS using the repeater function, that's why it's a problem.

Auto will include DFS mostly, so no, won't work. You need to set the right frequency, so all devices can handle it. The device with the highest requirements (in that case maybe the Opal, so no 160 MHz bandwidth, no DFS) is the one you need to adjust your Wi-Fi for.

Ok, I will try to set it to 42 just like you said.
Also I was just checking the infos of my home wifi and it showed me this

The channel is set to auto and the Opal can detect it with no problem

It can depend on many different things. Maybe Auto at your home gateway does not include DFS or maybe the whole issue is that at your works Wi-Fi 160 MHz is used.

Comparing all those settings will help you finding the root cause.

Ther are so many overlapping misconceptions in this thread that it's difficult to know where to start, but I'll try to explain some basic concepts and the (unavoidable) limitations of the various GL-iNet Travel Routers.

  1. Access Points (APs) vs. Clients (Stations - STAs). A WiFi Interface can operate either as an AP or STA. Think of the AP as the "Hub" broadcasting on a given Frequency (Channel). The Channel it uses may be determined automatically (Auto) or can be fixed to a specific configured Channel Number. An Auto setting may cause the AP to regularly (say once every 24hrs?) scan the local radio environment for other broadcasts and cause it to pick the least busy Channel at that moment, so the Channel Number used by an AP may vary over time. The interface will be configured with a specific network name (SSID) and authorisation mechanism (typically a WPA2 or WPA3 password) which STAs can Scan for and connect to. Once connected, if the AP changes channel number the connected STA(s) should follow it to the new channel. A decently configured workplace setting with multiple APs will have a carefully planned honeycomb matrix of AP radios configured with differing, fixed, non-overlapping channels in adjacent cells.
  2. WiFi "Adapters" or Radios - Each Adapter can support multiple Interfaces, so could act as both an AP and STA simultaneously. But a single Radio would (normally) only operate on a single frequency / Channel at any moment (this is a bit of a simplification as STAs may also be scanning for stronger signals on other channels). So when acting as a Repeater a GLiNet (or any other..) device acting as a router / firewall / VPN end-point will typically have one interface acting as an STA, pointing "upstream" and one or more interfaces, potentially Bridged together to act as a single LAN, as AP(s) pointing "downstream". The key restriction is the single-channel-per-radio. If a device (such as an GL.iNet Opal, Slate or Slate Plus) is not DFS-certified then it can't act as an AP on a 5GHz DFS Channel. However it can act as an STA, but the default GL.iNet menu system won't allow this unless you use LuCi as per my post (linked) earlier in this thread. You can also (with the LuCi workaround) use the router's 5GHz radio as an STA and the 2GHz radio as an AP for your devices, together with the Bridged Ethernet LAN port(s).
  3. Channel widths - The channel width (20, 40, 80, 160MHz), NOT number very simplistically, partly determines the maximum "speed" of a Channel (Google "Claude Shannon" if you want to know more..). However you may well, in a domestic setting, achieve better coverage and faster throughput with lower Channel Widths - especially on the noisier 2.4GHz channels, where it is almost always better and certainly more sociable to set 20MHz widths. The (excellent) diagram posted higher up the thread gives a good overview of the allowable combinations of Channel Number and Channel Width in the 5GHz band - but note that these can vary depending upon the local country!

Sorry for the length of this - a forum thread isn't really the place for basic WiFi info, so just search the Internet for the many, many articles that explain this far more effectively then I can!


Just changed to 40 MHz as you suggested to me and it worked, now the Opal can see the 5GHz.

Thank you guys for helping me to resolve this problem.

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Not sure if it is the exact and only reason. But glad that it works now.

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