WIRELESS TELEPHON Y—SLAUGHTER. 187 
from the telephone receivers. The design of a helmet which would 
accomplish this and at the same time not prove to be uncomfortable 
represents one of the most striking accomplishments in the complete 
set. 
AMPLIFIER 
TUBE 
DETECTOR 
REGULATOR 
Fig. 3.—Schematic diagram, airplane wireless telephone. 
) 
SWITCH 
(6 BLADES 
The adjustment of the receiving set is of the utmost simplicity, 
there being only a variable capacity and inductance to adjust for the 
