Thanks Craig,
I got tired of wondering so I pulled out the voltmeter and tested it. Trigger voltage = 189.8 and it works like a champ using just C cells. So if you're planning on using it on a digital device, you will need a peanut slave or a "safe hotshoe" adapter similar to the one marketed by Wein and others. Personally given the cost of the Wein device, I'd go with a peanut slave.
Jon