Coolerman:
Too late! I did it the old fashioned way. I didn't have a voltmeter, so I just took the plug apart. The only thing I found was a fuse, so I'm using an inline fuse. The step-down circuitry is in a little box between the power plug (now hacked off) and the output to the Nomad. I've installed it (details in another thread, soon to come) and it's working fine.
I'm still running into some noise issues, though. I'm using an inline filter to no avail. I'll probably end up trying some of your suggestions. The isolator sounds like it may work. One question: How am I supposed to ground the Nomad as it's plastic? There's no "frame" to speak of.
Thanks for your help.
Schlud:
Thanks for the suggestion. I've tried to upload a pic to the thread several times, but it hasn't worked. The image is <100 Kb. Is AF still allowing uploads? I'll figure it out soon, I'm sure.