Signal strength and connection

hi. i have mikrotik rb411 board include atheros 2.4ghz abg wifi card and 19dbi antenna and also have edimax ew7206apg installed 7dbi tplink antenna. i have problem with mikrotik.
there is an internet away from me. edimax shows me that signal strength %30 and it can connect (download speed 80-100kilobayte/s). but mikrotik shows signal strength between -95 and -91 and it cant connect. i tried everything to improve signal strength but i cant. my question is, why mikrotik not connecting that internet with 19dbi antenna ?.
sorry for my english. thanks

the rb411 only works on bridge or cpe mode no for multipoint at less than you use virtual aps, what distance are? what polarization is using? the cable loss? what mini-pci models uses?

la tarjeta rb411 solo trabaja en modo cpe y no como ap-bridge, a menos que utilices los virtual-ap, que distancia estas cubriendo? que polarizacion utilizas, ya verificaste los cables de rf? que modelo de mini-pci estas utilizando?
saludos.