YMMV ONN Digital Signal Amplifier for Indoor Antennas $1
I found a couple of these at a local Walmart for $1 each. Some locations are coming up for $3. Regular price $14.96. Check brickseek sku 139204884 for local stock and pricing. Check the clearance table in the tech section of the store. I found the small boxes in the middle of the table behind other merchandise. Link provided for product info only.