Hi Brian
Just read the article surprisingly a non-technical more historical description of these 1st mobile fire directory units. Here is the link straight to the Journal
http://www.ieee.ca/canrev/cr69/IEEEC...eview_no69.pdf .
I have followed this thread and the discussion of radar with interest as my father was an electrical engineer working on the development of Radar for the US Navy during the Second World War. Working on both ship board and ground mobile units.
Now I'll have to go digging through back issues of the IEEE Journal to see what other bits of historical interest may be hiding there.
Cheers and Thanks for sharing this link Phil