The TTFD was developed by the navy during WWII.
It seems "Buck" Rodgers developed it in 1958. His version with info can be found here.
EDIT: the link broke. A search for TTFD will take you to some good info. The diagram above with the formulas is basically all you need to build one. It has been made under several names. A search for FLAG antenna will find some good info also. The main difference between a TTFD and a FLAG is the way they are mounted.