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BELL SYSTEM TECHNICAL JOURNAL 



For parallel plane grids, we have 



l/)82 = (V2)Vsin2 {ej2) (10.8) 



where 6g is the transit angle between grids. We see that in terms of W 



and D we can write 



dg = diWD . 



(10.9) 



i 



0.6 0.7 0.8 0.9 1.0 I.I 1.2 1.3 1.4 



RELATIVE FREQUENCY, W 



Fig. 51. — Various functions of relative frequency W and relative spacing D plotted vs 

 relative frequency. 



Here B\ is the gap transit angle at a spacing d\ and a frequency TFi . So 

 that we may see the effect of tuning on 1//3-, WD has been plotted vs IF 

 in Fig. 51 and l//3^ has been plotted vs Qg in Fig. 52. 



We now have to consider losses. From (9.7) of Appendix IX we see that 

 the grid loss conductance can be expressed in the form 



Gg = GgyW^D^ (10.10) 



Here Ggi is the grid loss conductance a.t d = di and co = wi . 



Finally, let us consider the resonator loss. If the resonator could be 

 represented by an inductance L with a series resistance R, at high frequencies 

 the conductance would be very nearly 



