So the pigtail cable is TL-ANT24PT3

As fotodamaris mentioned, +8dbi omni antenna is not a right choice:(

The built-in antenna of TL-WA5210 is 12dBi directional antenna. While with this built-in 12dBi directional antenna you have found the signal not strong enough inside your room, let alone using the 8dbi external omni one. Moreover there is some signal loss on the 3 meter pigtail too.

For the signal issue, forget the 8dbi external omni antenna, use the built in one. Go to wireless menu, Enable High Power Mode, try the highest transmit power. Remember set back to the default in wireless settings when use the built-in antenna.

For the disconnect problem, try re-configure the 5210, better use different SSID and pass-phrase.

I have an omnidirectional antenna +8dB but it is not a TP-LINK and the antenna has been mounted vertically.
Without external antenna 5210G is working.
Why do you suggest to tilt down 5210G?
Here attached a schematic.




5201G has been already set up with max transm power.

Any further suggestions? I've to tilt down the 5210?
The clients are higher than the 5210

Is working yes, but with weak signal. This is the reason of external antenna

frankge973 wrote

Is working yes, but with weak signal. This is the reason of external antenna

So, better to uninstall external antenna and after how to tilt the device?

I do not want to have wifi emitters INSIDE home, so I brought network cable on ground floor (garden) and from there I used 5210 for creating a wifi from garden that can I use also with pcs, tablets, and so on at home

Safety