This film about Navy Blimp service has some cool radio scenes from 5:04 to 5:12, showing the operation of the GP-7 Liaison and ATB/ARB Command radios, as well as the antique equipment used by the Brazillian Air Corps fixed stations. http://imageevent.com/okbueno/mopic;jsessionid=vsp6efy1m2.eagle_s?p=49&n=1&m=-1&c=10&l=0&w=4&s=0&z=2