Their first joint patent describes a plan for accomplishing synchronized reception with transmission using a system of five relays interconnected to operate in successive cascade form; thus, when the relays at both terminals are correctly timed for successive operation, they will transmit and receive the five pulse combinations of the Baudot code. For transmitting and receiving the code pulses, each of the five relays has an additional contact. To start the relay cascade operation, a start relay is added at both terminals and operated by a start pulse which precedes each code transmission. It seemed natural for the Krums to turn to a relay system at first, since, from his work with the three-unit-code, high-low-voltage system, C. L. Krum was experienced with the possibilities of relay operation. The system of the relay chain in cascade operation was employed to operate a page printer using the mechanisms of the Blickensdoerfer typewriter which had a three-row typewheel. The Postal Telegraph Company became interested and bought a number of these printers in 1910. This was the first sale of Morkrum apparatus and provided enthusiasm for the Krums for further research, which led to the substitution of a governed-motor-driven brush distributor to replace the relay cascade system. For this new plan the motor at the receiving printer operated at a slightly higher speed and was held in continuously synchronous operation with the transmitter by the periodic transmission of a correcting pulse. The new code selecting and printer control system was also adapted to operate the mechanism of the Blickensdoerfer typewheel typewriter. The idea worked out better than the cascade relay system, and a number of printers using this method were constructed and named the “Morkrum Blue Code.” A few were put in service at the Postal Telegraph Company. The Associated Press (AP) became interested in the Morkrum “Blue Code” printer system as a replacement for the low-speed Morse system which was being used to transmit news items to newspapers in many cities. Here, continuous transmission under control of a code-punched tape, as used in the Morse code system, was a requirement, so Messrs. Krum set to work and designed a keyboard-operated, five-unit, Baudot-code perforator and an automatic punched-tape-controlled transmitter. This apparatus was installed at the New York headquarters in 1915 and receiving printers were gradually installed throughout the Associated Press system. The following excerpt and picture (fig. 6) from Oliver Gramling’s book, _AP—The Story of News_,[4] describes the introduction of the system to the Associated Press: