V. G. ELLERBRUCH, F. C. FITCHEN AND R. W. SAWREY 
nil 
Curve B 
151.0227 , 
151.008 
151.0214^ 
NOTE: All frequencies in MHz. 
L51.1209 151.0193 
Curve A— >s^51.113^ 
• 
151.118 
Figure 7. — Curves for crystals from two manufacturers. 
telemetry, the minimum drive level is signifi- 
cant. Data were taken where the crystal did not 
have sufficient drive to affect in phase mechani- 
cal motion and a rather strange curve resulted. 
The curve is plotted in Figure 8. 
The piezoelectric crystalline structure itself 
should not exhibit such characteristics, so one 
can assume that the electrode-crystal interface 
or the electrode size disrupts the usual well- 
ordered crystalline activity. This detrimental 
effect is especially significant at low energies. 
ILLUSTRATIVE DESIGN EXAMPLE 
For new designs there are always criteria 
set forth which must be met in order to satisfy 
