Hi all - a great book that has schematics, pictures, etc of 'spy' gear (European/Eastern Bloc/UK/US/Russia) is 'Wireless for the Warrior' vol 4 which has schematics of the PRC 77, Delco 5300, etc - (not the 74 though...) http://www.militaryradio.com/spyradio/index.html 73 de Mike