@terziyski 

It appears that my main wifi router (evolution digital) that was supplied by my cable company does not support onemesh or easy mesh. They have disabled the wps button as well

  @Ryan 

Thank you

That is what I ended up doing. But initially someone had said that it wouldn't work that way, that it had to be connected as a mesh network for devices to stay connected as I moved from the routers area into the extenders area.  But so far it seems to be working as one network

  @Blueshadow 

Linking a non "Mesh" router (like your router) with the RE220 extender will do what you want, as long as both use identical SSIDs & passwords (on one or both bands, 2.4 & 5 GHz). You should experience few problems if your devices don't move often within your house. For devices that move or those stopping/staying in an area where signals from your router and the RE220 overlap, then based on local factors (e.g. how much their signal-areas overlap, strength of signals, interference from microwave ovens/etc, neighbor's Wi-Fi/band congestion, etc.), such devices may switch once (or even flip-flop repeatedly) between your router and extender. During each switch the device will temporarily "lose signal" for maybe a second (but up to 3-5 seconds) while it "re-negotiates" its connection. If your apps buffer its received/streamed data, you shouldn't notice a degradation. But if you're sending data during a re-negotiation, your data will have slight delays/gaps and then will resume.

Devices on "Mesh" networks (like TP-Link's OneMesh and the industry-standard EasyMesh) should never (theoretically) ping-pong back and forth. That's because mesh networks keep track of where your device is (relative to each mesh-node), and intelligently decide which one node (the closest one) it will connect to at any time. Then when the device moves, that mesh-node will hand-off your device to another node as your device moves farther. Most mesh networks also use beam-forming to "aim" the Wi-Fi signal to a narrow area near your device, allowing it to "focus" the signal. They can do this with multiple devices simultaneously. Modern non-Mesh routers also use beam-forming.

If you don't move often within your house and your router & RE220 Wi-Fi signals are both strong, you should be fine.

  @HelpingOne 

Thank you

Yes, for my use, matching the extenders ssid and password to that of the main router should work fine.

The two main reasons I needed the extenders where for when Im outside on the back patio, the main wifi signal was weak there and cell phones would not stay connected and then I have an exterior security camera overlooking the driveway in the front of the house which always had a poor signal and would disconnect from the network ocassionally.

So, I wanted to extend my wifi signals to cover these dead spots. The security camera obviously never moves so once its connected through the extender that should rectify that problem.

So far, it seems to be working perfect.

I was initally told that naming the extenders with the same ssid/password as the maon router would not work, as the main router would get confused by the extenders and the extenders would stop working. The only way for them to work harmonisouly was if they were connected in a mesh network. I have only a basic knowledge in this area. But that advice didnt seem completely correct. So I posted here.

Thank you for your input

  @Blueshadow 

when you say you changed the password to match, how did you do that?
I have an issue and rather than post a new post, maybe the answer is in here.

I have 2 x TP Link RE200 extenders and the passwords were the same as my Vodafone WiFi password.

However, when one the the extenders stopped working, I looked in the app and saw that the password has changed...and it's now massive - about 50 characters long.

I'd love to change it back, but doesn't seem possible, so I was interested in your comment about matching the passwords.

Thanks

  @Blueshadow 

I was able to edit/change the SSID and password in the app