Hello all!
before writing here in this forum, I tried to make things work for 2 days, without success.
I just bought a TL-WA7210N but I have some problems.

My setup is as follows:
TL-WA7210N --> operation mode: Bridge with AP
Connected to:
Wireless 2,4 Ghz amplifier
Connected to:
Directional grid antenna ANT2424B

I'm running the TL-WA7210N in test mode, to test (obviously), at maximum power (27 dbm)
I changed in "Wireless advanced" the antenna setting to "External antenna"
I tested the wireless amplifier and the antenna by connecting them to my workstation: workstation --> wifi usb (AWUS036NH) --> amplifier --> antenna and both antenna and amplifier work very good

Simptoms:
When I go to Wireless --> Wireless settings, if I click on survey I can find my ap to connect to and I can connect to it with no problem (i.e. no problems with association with external ap).
Then if I go to Wireless --> Antenna Alignement I can see correct remote RSSI and Signal Percent

The problem is that I can't find my local wireless ap with my clients: note that TL-WA7210N, amplifier, ANT2424B, me and my clients are in the same room to test everything.
Note also that under Wireless --> Wireless settings "Enable Wireless Radio" and "Enable SSID Broadcast" are checked.

I tried different firmwares:
TL-WA7210N_V2_140730 (problem described above)
TL-WA7210N_V2_130320 (problem described above)
DD-WRT (I read it should work with only external antenna, but I have near no signal)
Openwrt (it works good with external amplifier and external antenna but the whole tx power is limited to max 16dbm....)

I have no problems with the internal antenna.

I also tried with this setup:
TL-WA7210N --> operation mode: Bridge with AP
Connected to:
Directional grid antenna ANT2424B

(no amplifier), and it works.

I don't know if the TL-WA7210N is defective and should be returned/changed.

I know some of you use external antennas so maybe someone can point me in the rigth direction.

Please do not reply with use "internal antenna": my setup must be TL-WA7210N + amplifier + ANT2424B

Why the WA7210N with tp link firmware cannot work with the external amplifier?

Thank you

Daniele