I live in an apartment made entirely of concrete and steel. I've manually configured the AP to transmit at the maximum power possible of 28dB.
Now, before ordering this unit, I did my research and found out that the LR unit had an advertised range of 180m(?). I'm getting quite poor signal strength only 70m from the AP. There are two concrete walls between the AP and my device. How can I possibly improve the range? Is there something in the setup process that I messed up or am not aware of? There's other settings like the channel set to AUTO/HT20 that I'm not well versed with since I've never dealt with networking gear before.
My apartment is huge with 4 big bedrooms on all 4 ends of the house and a hall in the middle. I can't place the AP in my hall due to the concealed wiring. It's all concrete and steel. I guess I'll have to buy another AP. Just wanted to make sure I was using every bit of the power the AP could provide.
Yeah there's not a lot you can do if you're trying to get a good signal through concrete and steel other than install more APs.
That HT20 thing is talking about channel bonding or whatever it's called. I'm not sure what the HT stands for but 20 refers to the 20mhz frequency range. You can set it to HT40 to use 40mhz, which would be like using channel 1 and 6. It will give you more bandwidth but will also interfere with other wifi in your area, although I doubt you'd be getting many other wifi signals getting in to your house by the sounds of it :P
It won't help much with your range or signal strength though, and it might give you less bandwidth especially if it's not supported by all your devices.
Seeing as I have this particular device and the regular non-LR model. The poor reception is due to the nature of 2.4GHz wireless band.
Indeed the LR does get close to the 183m rating (about 170m) in a sunny day scenario with nothing between the access point and client. However, place a few solid walls in the way and the story changes.
The particular property these are in is a barn conversion that has this crazy bubblewarp with foil on both sides of it as insulation and it is even within the interior walls. (essentially the whole god damn building is a faraday cage). However, higher frequency transmissions have no issue punching through the walls. Cellular signal is superb.
5GHz radio's have a much easier time of punching through obstacles, so in your case going to the UniFi AP Pro would be the better option. With the AP and AP-LR, two are required in my property however with the AP Pro only one is. (Due to its wall punching goodness). (Still use two due to the number of wireless devices though)
Also the UniFi stuff doesn't have the best performance in repeating mode (well pretty much any repeater sucks). So I would only consider a second AP if they will be connected into the same LAN backbone and the coverage zones overlap a bit so the client hand off can work correctly.
As for existing AP, other than what @Dexter_Kane has said, you won't get much more range.