Here's a Yahoo groups thing where the author has reached out for info from someone in the know (ultralight DX group)
Found this interesting:
"The problem is that Sony doesn’t want to cooperate much
with the article, as it associates their company with prison. That makes PR
people gun-shy. >>>
Sony's lack of cooperation is probably also related to the fact that their SRF-39FP model is based on mid-1990's technology, and is hardly a model that is likely to turn around their lackluster financial situation."
There's also more technical info on the radios there as well.