Well 1 more adapter ticked off the list!
I now have a cable to connect your Stilo Helmet to a TerraPhone intercom. This cable has the same electronics built into it that the Peltor to TerraPhone adapter utilizes. Check it out on my website.
Anyone local to San Diego have (or willing to snail mail me) a Terraphone intercom --> Peltor headset adaptor I can borrow next weekend for the Ensenada Rally?
I left my adaptor in a car I co-drove in, and the adaptor seems to have gone AWOL.