[SOLVED] Xiaomi Router Without Proper Shielding?

[Boris_yo]

Hello,

Was thinking about getting Xiaomi Mi 4A Gigabit Edition router and wondered if its firmware can also be rewritten with OpenWRT. When checked I noticed a warning message:

What is this shielding thing? How bad is it in this router? There's also warning about incapability of OpenWRT to work with certain chip. No way to know what kind of chip will be in my router before I buy?

 

[bill001g]

Pretty much that is a tplink c6 v3.

TPlink also changes the internal chips all the time and there is no way to tell until you open the box, maybe you get lucky and they change the version number. This is why I tend to never recommend exact hardware when someone is planning third party firmware.

It would not be uncommon for any vendor to change the manufacture of the chips if there was some kind of shortage. As long as the factory firmware works they really don't care.

It is actually very fortunate that you found that warning. It seem this is a very new thing and Xiaomi is not as common a brand so you do not get as much info.

I would not take the risk. I know of no way to know what chips are on the inside. I know when I did this long ago on tplink I had to go into the store and look at the UPC codes to be sure I did not get burned.

It also depends on why you are running third party firmware. That router is not very powerful and depending on what feature you are using in the third party firmware it can easily bottleneck many faster internet connections. If you want something to play with there are many raspberry pi based routers that are actually cheaper.
All the really fun stuff related to wifi is all locked up in wifi chips and you only get some binary image that you can not change you load into the chip from the router firmware.

 

[gggplaya]

If you have an old x86 desktop laying around, you can buy some used NC110T Intel server ethernet cards and load OpenWRT onto it. Then you run CAKE or FQ_Codel QOS at full gigabit or higher speeds.

You don't need alot of ram, maybe 2GB. You don't need a hard drive either, I just run it from a USB stick.

 

[Boris_yo]

It also depends on why you are running third party firmware. That router is not very powerful and depending on what feature you are using in the third party firmware it can easily bottleneck many faster internet connections. If you want something to play with there are many raspberry pi based routers that are actually cheaper.

3rd party firmware is not the goal. It's just added convenience for me to have something to play with in case stock firmware will cause issues or something. Do you know what is that message about Xiaomi shipping units without proper shielding since 2020?

 

[gggplaya]

Yes, they are cutting corners. I would stay away from them. If they aren't properly shielding their circuitboard, you could run into radio interference issues or a higher noise floor which will reduce your range.

 

[Boris_yo]

@gggplaya Does it generally cause interference in 2.5GHz or 5GHz band that affects neighbours routers, FM radio at home, hearing aid, TV wireless radio listening system? Any chance it cause interference for pacemaker?

 

[gggplaya]

There's a picture on this thread: https://forum.openwrt.org/t/feedbac...er-switch-patches-please-close-thread/78468/3

The lack of shielding wouldn't cause interference with other objects in your house because it's not putting out that kind of power from these components. Perhaps if some of those devices were directly next to the router......

But the shield problem is more of an issue in regards to the router receiving interference and noise. This will affect performance of the router itself.

 

[Boris_yo]

@gggplaya Most people on YouTube report good wireless operation of device however one or two reported that signal is not as they hoped. Maybe it's okay for 70 square meters apartment. I don't know. I have 2 doors from a room with router.

 

[gggplaya]

It's probably fine for an apartment since apartments aren't that big. But the noise floor of the transceiver circuit will be higher. Which means when your client device is trying to send signal to the router from a far distance, the signal strength must be higher than the noise floor for the router to receive it. The router can't operate down to as low of a signal strength. Which TLDR means you can't travel as far away from the router.

 

[bill001g]

You need to release that most people on youtube are idiots. Most people that have strong knowledge about wifi and other networks stuff do not waste their time on making videos on youtube. It is a bunch of people that either want to be popular or just want to make money by posting stuff they find with google.
The vast majority are just personal opinions based on nonscientific data. I mean maybe I should make a video that say a router works best when you wear it as a hat.

This is hard to say what running without shielding will really do. It likely does not mean it transmits interference, they would lose their FCC certifications if it did. It likely means it is more susceptible to interference.

If you have concerns about this why even mess with it. I mean the tplink c6 v3 is the same device and from what I can tell cost maybe $10 more. There are many other routers that support third party firmware and if price is a concern just buy a used router. Lot of people chasing the newest tech so older stuff that works perfectly fine is on the used market.