Disconnection problems

thanks for the reply earlier on.

i have changed the card in the enclosure to XR5 frequency at 5300,connecting to 24dbi grid antenna.
this is set in station mode.

my AP is running also on an XR5 connecting to an omni.at first frequency was at 5300 but seem more people are
using that so i changed to 5240.
checking my signal from AP side its like this:

signal strength -76dbm
Tx signal strength -78dbm
signal to noise -22db
Tx/Rx CCQ 74/71

the setup at the client side is we installed a 15m pole the grid is at the top.the ground in low that side so we can’t see
the AP.we tried to get the signal thats the one i’ve said.their are a couple of big trees with leaves not directly in front.
and as of the weather its just started getting too hot.