Building a vibrating table

I'm in the process of drawing up plans to build a vibrating table and was wondering if anyone could help me figure out what the appropriate horsepower for the motor is. I have to order the motor online and have no way to feel how strongly it vibrates before buying it. I know that heavy duty shakers for concrete are in the 1 HP and up. I'm looking at some that are 1/100 HP. This table is not going to be huge or need to shake a heavy load, but the little lab vibrator I'm using is just slightly underpowered for my liking.
If you know off the top of your head, or if anyone has a vibrating table and can read the spec on the motor, I'd greatly appreciate it.

Thanks,
Mike