Glad I could help. If you can improve your WLAN, maybe you want to give feedback here in this thread.

Wish you much success and fun with Omada EAPs!

BTW, I had an idea how to help your camping guests coming with Faraday Cages on wheels to get better WiFi reception:

You could lease or sell them a CPE510/210 to connect to the WLAN and use it on their laptop wired to the CPE. See this post of a camping guest who uses the method to create an own network in his RV. CPEs can be used as wireless clients - or even as wireless routers creating a whole subnetwork for people carrying their data center in a RV.  

Yes, EAP225-Outdoor has 360º dual-band antennas. CPEs have directional antennas: CPE210 has 65º, CPE510 has 45º beam width.

RiversideCamp wrote

I then took it back to the remote location, mounted it back on the roof, and ran Speed Test. I got a 47.9 Mb download. Then a minute later it was 1.7 Mb, then nothing. It now shows "isolated" on the Omada controller software and I can't get it to do anything. It seems to me that the signal should be OK since I got almost 48 Mb on the first test, so what happened?

Difficult to say what caused isolation after it did work already. I recommend to set 802.11n/ac WiFi mode for the 5 GHz radio (click on Access Points, then the Outdoor EAP listed there, then Configuration in the pop-up menu, then Radio/5 GHz). You can also try to set channel bandwidth to 40 MHz or 20 MHz. Next, ensure that there is a free LoS between both APs, this is very important. Make sure that the antennas are screwed on tightly (they tend to loosen when you adjust them) and are aligned in parallel. Maximum allowed Tx power in the US should even be much higher than in the EU, so 100m distance should be no problem.

Are there many vehicels in-between the EAPs? Are the EAPs mounted on the same level over ground (or nearly the same level)?

Did you turn off the controller or is it still running? As I wrote, turning off the controller should be supported for meshing after initial setup according to TP-Link's FAQ, but I never tested it, so I can't say whether the FAQ is right here.

And to make matters worse, apparently TP Link provides absolutely NO support for this product on nights or weekends, since it is classified as "business" product and they only support "home" products after hours. I really wish I had known this before purchase.

 

Oops, it's new to me that your TP-Link branch office supports home products over nights or weekends (the branch office in my country doesn't do so). Business-class products are supported here, but only by mail (as are home products).

RiversideCamp wrote

There is clear Line of Sight between the devices. The first is mounted at approx. 15' agl, the second is probably closer to 11' agl, but not a huge difference. There are no vehicles inbetween them, although there are vehicles below the sight line between the locations, not sure if that's what you meant? Nothing obstructing Line of Sight.

What is 15' in meters? Yes, I meant vehicels on the ground, they will also reflect microwaves, possibly creating interferences.

So you recommend setting 5g? I had heard 2.4 has better distance coverage, is that true? Right now it is on both

 

No, you should leave both, 2.4 GHz and 5 GHz enabled, but the mesh always uses the 5 GHz band to link the nodes. 2.4 GHz can pass obstacles such as trees much better, but 5 GHz offers a greater range and better channel separation leading to more stable links.

Also FWIW, in the office, approx. 50' from the AP that is working, I'm only pulling .24 Mbps up and down right now. It seems to vary wildly, from 50 or 60 to 1 or 2 just a minute apart. 

 

Yes, I told you. Radiation of EAP's omni antennas is 360º, but not as an ideal sphere, it rather radiates like a donut. There is a good signal all around at the height level of the EAP horizontally, much weaker signal directly beneath it (vertically). Radiation expands vertically the further the signal travels horizontally.

This is the throughput in my office via EAP225-Outdoor mounted on the balcony ~3m apart, ~2.5m above. There are 2 walls between, thus no free LoS, bandwidth is further rate-limited (in the switch) to 160 Mbps downstream/8 Mbps upstream:

Is there a change to get mains power on the camping ground? Could you test the second EAP at a location nearer to the office house?

Ok, I just did set up a mesh node. Connected it to the controller by wire, adopted it.

Then I isolated it, only power supply feed to the remote node. It goes to state »Isolated«.

Proceed as follows:

1. Login to the controller.

2. Go to tab »Site Settings« (bottom of screen), click on »Device Account«. Show the password, make note of Username/Passwort (needed later).

3. Next, go to tab »Access Points« (top of screen). There should be one EAP in state »Connected«, the other (remote one) in state »Isolated«.

4. Click on the MAC address of the remote EAP so that the pop-up for configuration appears. Select »Mesh«. It should look similar to this:

5. Click on »Retry«. A pop-up appears asking for username/password. Enter values from step 2 here.

6. Now wireless adoption happens. This may take a while. If successful, the Action button shows »Linked«, status still »Isolated«:

7. Just wait a little until it will show »Connected«. Done.

The normal way is to adopt them wirelessly at first time, no wired connection needed at all (only exception is if you use mamangement VLAN, but that's another story).