Hi!
I have Mikrotik RBD53G-5HacD2HnD&EG18-EA (Chateau LTE18) installed in my house. Unfortunately wifi coverage within premises is not so good, so I want to improve it.
Can you please suggest me Mikrotik "range extenders" (or whatever you call this device) .I am not networking guru, but I hope you understood what kind of device I want to obtain.

Define "small" (a single access point should normally cover a "small" house, unless it is not so small or it has a strange shape or the placement of the existing device is non-optimal).

Mikrotik "range extenders" do not really exist, in the sense that any wifi mikrotik can be configured as range extender, but there are limitations that you should be aware of (unless you can run an ethernet cable from the Chateau to this added device, and then it would be a simple Access Point).

With devices with a single radio bandwidth/speed will be halved (because the same radio half of the time transmits and receives to and from the Chatesu and the other half of the time transmits and receives to and from clients).

With devices with two radios you can use one radio as "station" (Mikrotik word for "client") and one as Access Point, speed will be determined by the slower of the two radios, choosing which to use as station and which as AP depends also on the way your devices connect (if you have older 2.4 GHz only devices you would need to use the 5 GHz radio as station and the 2.4 GHz as AP, if your devices all connect to to 5GHz, you could try viceversa).

There is an exception, the Audience, which has three radios (and thus you can use one of the 5 GHz one as station connected to the Chateau and have as AP both a 5 GHz and a 2.4 GHz radio):
https://mikrotik.com/product/audience
but that is not particularly cheap and not particularly fast, when compared to other wifi 6 devices like your Chateau.

You should better detail your requirements so that some more targeted advice can be given.

I have 4g router and due to this I can place it only in one specific place (for best signal from tower because I dont have possibility to use external antennas) which is not optimal for wifi, so router is placed not in the middle house but closer to one corner.
Issue is that 3+ meters from router wifi signal is really bad. So I want to place extender in around 1-2 meters from router. I cannot use cable, so can connect extender only using wifi. All my devices use 5Ghz.
Do I understand correctly - if I use any Mikrotik router as "extender" and this router has 2GHz/5GHz wifi, this will result that one radio will work as station (will be occupied only for connection towards Chateau) and other band will work to serve internet further?

The other thing now is not clear for me. If I have Chateau and any Mikrotik AP, re-connection to AP will work seamlessly when I leave coverage of Chateau? How e.g. my phone (while I am walking through home) will determine that it is time to switch to AP instead of router?

Yes, one radio in one direction and the other in the other direction, but it is not compulsory, it is just the usually advised setup (as it is usually faster than using a single radio).

In theory yes, Ax drivers are reported to work well at roaming, of course if properly configured, though some devices are reported to have stability issues with latest-latest versions, slightly older Ros versions seem to be solid.

I am not at all familiar with the Chateau, but 3 meters of "good" signal only sound really strange, there might be some issues either in the device (hardware) or in the configuration or software.

Depending on the shape of the house, how walls are placed, etc. It could be possible to use a more directional device, like the Wap Ax, instead of an omni-directional one like - still say- the Cap Ax or an AX2 or Ax3.

Let me add details. I haven't played with wifi configs, only changed wifi names and passwords, all other is the default.
When I speak 3 meters, connection from router goes through two aerated concrete walls. And client laptops (running windows) reports only one wifi "stick". This applies both to 2GHz and 5GHz connections.
I am running latest RouterOS. Can you please suggest wifi settings which I can have a look at and adjust for better wifi signal strength?

While I was exploring device options you shared, I noticed one specification called "number of chains", some devices have 1, some - 4. Does this option somehow help in my original question?
As well, while checking those devices, I wasnt clear which of them are directional and which just works as router (spreads wifi signal evenly around).

2 concrete walls over 3 meters ? That's a wifi killer ... forget about using wireless backhaul too then. It will not be reliable enough.

If cable is not an option, already considered PLC devices (powerline) to act as network cable ?
Only possible if both sides are on the same phase of your power network.

MOCA ? Ethernet over coax.

Really no way to have a cable added, not even when going from outside ?

There no settings that can make wi-fi pass through concrete walls, there may be some fine tuning, but one way or the other you need to rethink the placement of your wi-fi source.

Since it is a small house, surely you have a single phase AC mains with a single electric box, so a powerline adapter to "connect" the Chateau to the new device is a very good idea.

Speed over powerline is usually not the best you can have, but recent devices are actually quite fast.

The "theoretical" setup for wi-fi (what very few people have or can have) is to place an omni-directional device (example among the mentioned ones the Cap AX) in an elevated position (ceiling) in the center of the house, what will be covered is a circle (so all the house) with better reception where there is direct line of sight to the device, walls, particularly reinforced concrete ones, are obstacles of course, the "best" house (for wi-fi) is a single square room divided by Japanese paper walls .

What most people have is instead a (still omni-directional) device like the HAP Ax2 or AX3 (or your Chateau) on a (low) shelf along a wall, generally speaking this also works fine because a part of the emissions is reflected by the wall immediately behind the device.

A more directional device, like the Wap Ax, sends signals in an offset circle, which covers with the strongest signal - roughly - an angle between 90 and 120 °, that makes it a very good device to place in a corner, as most of the power is directed forward.

In more complex cases multiple access points are needed but where they are placed (or can be placed) makes a lot of difference.

If you have a (even rough) drawing of your house, you can try using (a few are free) simulator to find what the best placements could be, but it is not much more accurate than what you can do with some common sense and a compass, at the end of the day the characteristics of the walls and the effect of reflections can only be determined by trying the device(s) on the field.

Mikrotik does not make (anymore) powerline adapters, a reputable maker is Devolo, which recently made very fast adapters, see:
https://www.devolo.global/magic-2-wifi-6
the Magic 2 starter kit is not exactly cheap (should be available for around 230-260 Euro), but more modest (probably still fast enough) adapters like the Magic 1 are roughly half that price.

TP-Link has also several lines (cheaper), the tl-wpa7817 kit should be around 70-80 Euro.

The advantage of a powerline (compared with a MOCA that needs anyway to re-use an existing, old, coaxial cable) is the possibility to experiment freely with the placement of the access point, basically one of the two devices injects internet on the whole electrical plant of the house and the other one extracts it from the electrical socket you connect it to, so basically you can place it anywhere you have a socket (and you may later add a second access point if needed).

If I were you, I would invest the 70-80 Euro on a cheap device like the tp-link and see how it behaves, very likely it will solve your issue or at least it should show if it is the case of investing more money on the approach.

Devolo makes also a three phases adapter (to be installed in the "main" electric box) but it should not be needed in a "small" house (it depends on how the plant is made, in EU many (most?) countries use generally single phase in apartments, but in some countries (Germany as an example?) three phases are used.

Speed over powerline is usually not the best you can have, but recent devices are actually quite fast.

The only real problem I have personally encountered using powerline adapters is when there is also a solar convertor system on the same phase.
The block wave harmonics used to create AC-sine wave can really impact your network speed when going over those same AC-lines.
But then I am talking about a drop from 300-400Mbps down to about 80Mbps and that was all observed at least 5 years ago (CAT6 cable installed via garage and basement solved that little first world problem).

Could be more recent PLC products are much better handling those interferences now.

Yep, but there are many factors that may (or may not) influence the "quality" of your mains and - indirectly - the speed of a powerline, a solar converter can be one but also (say) old (but powerful) motors (only as an example old lifts/elevators ones) or - more generally - lots of inductive (as opposed to resistive) loads.

Nowadays almost everything you plug in a socket or connect to mains (exception made for ovens, electric heaters, hair driers and similar) tend to be inductive, in the (good?) ol' days all or almost all lighting was resistive (and that helped by generating no harmonics), since the advent of CFL's and leds it has changed, though in most cases of normal homes the effects are not that much relevant.

Though I don't have recent experience with the top speed ones, the powerlines that were available three or four years ago were much better (besides increased speed) than the earlier generations ones, though still nothing can beat a good ethernet cable powerline is IMHO still a better choice than (poor) wi-fi.

Thank you, guys! I've ordered TP-Link Starter Kit TL-PA7017P. This was the cheapest option available in our market. It will arrive in around one week.

Thank you, guys! I've ordered TP-Link Starter Kit TL-PA7017P. This was the cheapest option available in our market. It will arrive in around one week.

Wait a minute, that one has no wi-fi , it is a plain ethernet kit.

You will still need an access point connected via ethernet to the device not connected to the Chateau.
(which could be a good thing as you have more choices for "plain" access points, Tp-link, Mikrotik or other brands).

Check the page:
https://www.tp-link.com/en/home-networking/powerline/

the kits with wifi are the ones with the "wi-fi" in the description , the ones missing that are ethernet only.

Excuse me, I pasted wrong product. I've ordered TL-WPA8631P KIT, this comes with wifi.
https://www.tp-link.com/baltic/home-net ... 8631p-kit/

Excuse me, I pasted wrong product. I've ordered TL-WPA8631P KIT, this comes with wifi.
https://www.tp-link.com/baltic/home-net ... 8631p-kit/

Ahh, good.

There would be no problem with a wired only version, just plug in a wifi AP at the other end............