A:Answer An extender needs to be placed in a location/position that has a solid signal from the source... it then repeats the signal further along. If it grabs a weak signal, it will repeat a weak signal. If you cannot place the extender in such a location, it is not an ideal solution.
I would look for a higher powered wireless adapter with an external antenna that you can position high up on a shelf, and maintain a good Lin Of Sight to the source signal.
Position is everything, you may do well just experimenting with the placement of your existing antenna/adapter.