308 



alternator shaft is a small direct current 

 exciter. Engine and alternator are 

 situated in a separate room from the rest 

 of the apparatus. The engine is water- 

 cooled by rain water collected in a large 

 tank outside. The receiver consists of 

 a Telefunken loosely coupled set with 

 variable condensers, telephones, two 

 sensitive Galena detectors and transfer 

 switch. To the left of the receiver stand 

 a high voltage tube condenser, the 

 quenched, and variometer inductances. 

 A hot-wire ammeter is included in the 

 antenna circuit. 



It is remarkable that this small station 

 can work with Vera Cruz, over 

 mountains and dry places, a distance of 

 nearly 800 miles, but strange things hap- 

 pen in the tropics. 



Pojpular Science Monthly 



A 



A Variable Condenser 



VARLA-BLE condenser can be 

 made of two test tubes covered out- 

 side with tinfoil, one tube being a little 

 smaller in diameter than the other. The 

 smaller tube is placed inside of the large 

 one, a flexible card being attached to 

 the tinfoil on each. The condenser is 

 varied by sliding the smaller tube 

 in and out of the larger. There 

 may be several sets of these condensers 

 made and hooked up in either parallel 

 or series. 

 lor^e tube cohered m'fh fo// on oiyfj/de 

 I 



Jmo// Me coi'ered iv/fh fo//on i 



A variable condenser made from two test tubes 



Radio Club News 



THE Technical Association of Li- 

 censed Operators, was formed on 

 October 21. 1913. Meetings are 

 held fortnightly, at which papers are 

 presented and discussed. The present 

 officers are : W. Woodrow, President ; E. 

 T. Dickey, Secretary and Treasurer. 

 Other clubs are invited to address 

 communications to the secretary's of- 

 fice, 1649 Amsterdam Ave.. New- York 

 City. 



Radio Club of Redlands 



The Radio Ckil) of Redlands, Calif., 

 was recently formed, with an initial 

 membership of nine. The following 

 officers were elected: President and 

 Chief Operator. Ezra Moore ; Vice- 

 President, Arthur Munzic ; Secretary- 

 Treasurer, Rudolph Kubias, and Asst. 

 Secretary-Treasurer. Harry William- 

 son. Meetings are held every second 

 Friday evening, at 7 :30 P. M. 



Amateurs in nearby towns are re- 

 quested to communicate with the club, 

 at 108 Eleventh Street. Redlands, Cal. 



Wireless Club in Salt Lake City 



At a recent meeting officers were again 

 elected to positions in the Granite Wire- 



less Association. The club is beginning 

 its second year in amateur radio work 

 and is now studying some of the latest 

 works on Radio under the supervision of 

 Prof. S. H. Besley. Most of the mem- 

 bers have stations entirely of their own 

 make and have secured excellent results. 

 They hope to have the largest club of 

 the Middle West and invite communica- 

 tions from other clubs. These may be 

 addressed to Pres. Merton Stevenson, 

 Granite High School, Salt Lake City, 

 Utah. The club's station call is G. W. A. 

 and practice work is carried on the last 

 Saturday evening in each month. Busi- 

 ness meetings are held every Friday af- 

 ternoon, beginning at 2 P. M. at the 

 school building. 



Pensacola Junior Radio Club 



The Junior Radio Club of Pensacola, 

 Ma., recently held its first meeting. The 

 following officers were elected : Edwin 

 Copas, President ; Oliver Williams. Sec- 

 retary; Fred Gillmore. Operator. Near- 

 by amateurs are invited to join. Ad- 

 dress communications to PVed Gillmore. 

 127 W. Gregory Street, Pensacola, Fla. 



