In the fall of 1915, he began teaching a radio principles class at the local Y . M . C . A . Tuska also began experimenting with radiotelephony, using an arc transmitter of his own design which employed tungsten electrodes to make audio transmissions.
22.
CEVNI contains the core uniform rules applicable to the traffic on inland waterways, such as visual signs on vessels, sound signals and radiotelephony, waterway signs and markings, rules of the road, berthing rules, and prevention of pollution of water and disposal of waste.
23.
Maritime Telemedical Assistance Service can be requested by messaging " HD MEDICO XSV " on Ch 16 radiotelephony ( preceded with PAN PAN for urgent cases ), or radiotelexing MED + " ( prefixing XXX for urgent cases ) to 2012 XSV CN on 2082 kHz.
24.
In 1916, operating under a personal Special Amateur license, 1ZT, Tuska began experimenting with radiotelephony, using an arc transmitter of his own design which employed tungsten electrodes to make audio transmissions, and by March of that year was broadcasting semi-regular phonograph concerts.
25.
Modern radiotelephony and aviation uses spelling alphabets ( the best-known of which is the NATO Phonetic Alphabet, which begins with " Alfa ", " Bravo ", " Charlie ", " Delta " . . . ) in which the letters of the English alphabet are arbitrarily assigned words and names in an acrophonic manner to avoid misunderstanding.
26.
This is also useful in radiotelephony, or even when ships are within hailing distance, if there is no common language : a crewman on a burning ship yells " yuliett alfa vour ", and a vessel coming to their aid knows exactly what they need " material for foam fire extinguishers " ( that is, the foaming agent ) . ( See : de : Flaggenalphabet for the German version of single-letter signals .)
27.
Other major electronic imports during the period were : parts and accessories of other telephonic or telegraphic apparatuses ( $ 391.99 million ); other accessories for the manufacture of semiconductor devices ( $ 336.31 million ); telephonic switching apparatuses ( $ 247.07 million ); transmission apparatuses for radiotelephony, radio telegraphy, and radio or television broadcasting ( $ 225.98 million ); and other electronic integrated circuits and microassemblies ( $ 195.80 million ).
28.
The code also covers procedural aspects ( how to initiate a call, the format of a message, how to format date and time, etc . ), how naval ships ( which usually use their own codes ) indicate that they are using the ICS ( by flying the code pennant ), use in radiotelephony ( use of the spoken word " Interco " ), and various other matters ( such as how an aircraft directs a vessel to another vessel in distress and how to order unidentified submarines to surface ).
29.
In a series of tests conducted at the U . S . Army's Langley Field in Hampton, Virginia, in July and August 1917, the world's first " plane-to-plane " and " ground-to-plane, and vice versa " communications by radiotelephony ( as opposed to radiotelegraphy which had been developed earlier ) were made to and from modified US Army JN-4s by Western Electric Company ( Bell Labs ) design engineers Lewis M . Clement and Raymond Heising, the developers of the experimental wind generator-powered airborne wireless voice transmitter and receiver equipment.
