Problem is at is follows.
Living in building with internet access given by owner.
Because main router cannot cover all building, extender is in place.

Now, my PC "sees" network and connects to extender.
But, extender crashes often and I would like to connect to main router. Using inSSIDer, I can see both networks, but how to force OS to do the same?

Both networks are on same SSID, same channel, only difference is MAC address and signal strength. Using TP LINK TL-WN722N USB dongle as adapter, drivers are supplied from MC.

Sorry for possible errors in post, I'm not a native English speaker