I drew a diagram of the set up I would like to have at home. Basically my ISP has locked me out of my primary access point, ever since I switched to fibre and they installed a new router. They say "we do not offer access to the new access points, if you have any issues give us a call [on a "support" line we charge you for using]".
I have a new SmartTV in the other room and I have bought two powerline adapters to get LAN throughput for it, since we will be streaming HD and 4K content (plus, the building is reinforced concrete, so not great for WLAN). Once I paired the powerline adapters, they work fine and I have connected the other end directly to my TV for now.
However, the wi-fi barely reaches the TV room and it's a constant struggle, sometimes it's hard to even queue a youtube clip from my phone to the TV. My idea is to connect the LAN from the powerline to my old but trusty Linksys WRT160Nv3, creating coverage for the other part of my home, and connecting the TV directly to it with LAN once again, for better performance (the powerline adapter, WRT160N and would be both behind the TV).
I have flashed a bios from DD-WRT to it, I forgot which version, but the BIOS says "DD-WRT v24-sp2 (08/12/10) mini -build 14929".
Tthen followed the instructions from here. However, I had to guess some of the settings like "Wireless Network Mode", "Wireless Security" (WPA2 Personal vs Personal mixed, etc), "WPA Algorithms", because I don't know how the first access point is set up, and others like "Channel Width", because the guide does not mention them. For the IPs I used 192.168.100.1 for the gateway and 192.168.100.2 for the local IP, as shown on the diagram (there was no device with the .2 IP at the time, I checked). I also connected the incoming LAN cable (from the powerline) to one of the LAN ports, not the Ethernet (in) port, as I read in the DD-WRT guide.
Following this I restarted the router and it accepted the new settings (the wireless name was the same as the other wifi, there was basically one network from both routers), but there was no internet, when connected to it and I could not ping the first router, when connected to the WRT with a LAN cable.
What should I do? Is this (Repeater Bridge) the easiest way of doing it? I think I read somewhere in the guides in DD-WRT that the client bridge is easier to implement? Can this be done without access to the first router, just with the information I was able to grab from the wi-fi scanner app? I also don't mind calling up the ISP and asking for any details, but I am unsure if they know where to find what I am looking for and whether they are willing to tell me. Alternatively, is there an easier way of doing it, even if I have two networks, e.g. Wifi-1 and Wifi-2? I don't mind that at all.
If the repeater bridge is the right way and the only way, I can give detailed information on how I set up the router, since maybe some of the guide information does not apply to me or I guessed something wrongly.