(...) Yes, I would be susprised if you'd find anything like this - at least for a year or two. But I can tell you how I would do it if I were so inclined: (Warning, technical dicussion follows) I'd take a BalloonBoard ((URL) and put a CompactFlash (...) (21 years ago, 12-Feb-04, to lugnet.trains)
Forget 802.11 WiFi, just use Bluetooth for a job like this. Have a bluetooth box somewhere on the layout and bluetooth inside the carrages with small batteries. Not that I know much about Bluetooth but what I have seen suggests its for these small (...) (21 years ago, 12-Feb-04, to lugnet.trains)
