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tween the carbon granules and the electrode surfaces and between 

 the granules themselves, in all of the positions in which the transmitter 

 is likely to be held while in use. This uniformity of contact pressure 

 makes the resistance of the transmitter nearly independent of angular 

 position as shown by Curve A, Fig. 5. 



Fig. 6 — Cross section of a typical deskstand transmitter. 



The substantially uniform resistance of the present handset trans- 

 mitter in various positions represents an outstanding improvement 

 over that obtained with a typical deskstand transmitter such as that 

 shown in cross-section in Fig. 6. Referring to curve B, Fig. 5, it will 

 be observed that the resistance of this transmitter is markedly de- 

 pendent upon angular position, two prominent peaks occurring where 

 the electrodes are practically horizontal and the carbon falls away from 

 the surface of the upper electrode. This is typical of the performance 

 of the older types of transmitters employing the conventional form of 

 direct action structure. While this characteristic is not important in 



