If you are in Providence, any decent digital antenna should work. Put your info into rabbitears.info to get a map of what direction to point it, and try and put it in your attic or roof. The Channel 10 broadcast antenna is close enough that you should pick it up without pointing towards it. And a wide recieve antenna should pick up all the Boston stations - you don't need a yagi style.

I have a cheap antenna in my attic and pick up everything. On my mother's house in Bristol I used a yagi to guarantee reception of Boston stations and because the channel 10 broadcast antenna was within the 30 degree reception cone of the yagi antenna along with the Boston stations.

Those window mount flat ones are asking for disappointment if you want to pick up channel 5.