So I found an old Vivitar 3700 flash in my dads pile of photo gear. Looks to have been made ~1980ish and after a bit or cleaning and a solder job (obviously an old set of batteries had been left in for waaaaaay too long) it works just fine. Well, it flashes anyway. I did some google-fu and got worried as the voltage levels at the shoe are ~9VDC and I wonder if the E-P1 might not quite like that too much (I didn't put it on yet). I plan on using off camera anyway so what I'm wondering is will the Hot Shoe Flash Cable (FL-CB05) provide some type of isolation from the high voltage or is it just a patch cord? I don't see anywhere to connect a PC sync cable and I'm not really interested in anything fancy (like wireless/IR, etc) and the Vivitar 'manual' I found makes no mention of optical slave functionality. Any insight or suggestions on getting a basic off camera (via cable) operation going would be most welcome.