REFLEX OSCILLA TORS 461 



Ea Retarding field in drift space. 



F Drift effectiveness factor (5.4). 



G Conductance 



Gi, G-2 Reduced conductances (9.6), (9.12). 



Ge Gap conductance of loaded resonator. 



G< Electronic conductance. 



Gl Conductance at gap due to load. 



Gr Conductance at gap due to resonator loss. 



H Efficiency parameter (3.7). 



Hm Maximum value of // for a given resonator loss. 



/ Radio-frequency current. 



h Current induced in circuit by convection current returning across gap. 



h D-C beam current. 



A' Resonator loss parameter (3.9). 



A" Radiation loss in watts/(degree Kelvin)'' {k-2). 



L Inductance. 



M Characteristic admittance (a-8). 



Ml Characteristic admittance of line. 



Ml/ Short line admittance parameter (9.38). 



N Drift time in cycles. 



N Length of line in wavelengths (Section IX only). 



N Transformer voltage ratio. 



P Power. 



Q Equation (a- 10). 



Qe External (? (a-11). 



Qo Unloaded Q (a-12). 



R Surface resistance (o-2). 



5 Scaling factor (9.17). 



T Temperature. 



V Radio-frequency voltage. 



V Potential in drift space (Appendix VI only). 

 I'o D-C beam voltage at gap. 



Vr The repeller is at a potential (— I'r) with respect to the cathode. 



W Work, energy (Appendix I). 



W Reduced radian frequency (10.5). 



A' Bunching parameter (2.9). 



V Admittance. 



Yc Circuit admittance. 



I\ Electronic admittance. 



Y L Load admittance. 



Y R Resonator admittance. 



Z Impedance. 



Zl Load impedance. 



a Distance between grid wire centers. 



d Separation between grid planes or tubes forming gap. 



e Electronic charge (1.59 X 10''^ Coulombs). 



/ Frequency. 



/ Factor relating to effective grid voltage (b-37). 



i Radio-frequency convection current. 



72 Radio-frequency convection current returning across gap (c-4). 



{12) f Fundamental component of /•> . 



j V-1 



k Boltzman's constant (1.37 X 10^^ joules/degree A). 



k Conduction loss watts/degree C (yfe-14). 



/ Length. 



m Mutual inductance. 



;« Electronic mass (9.03 x 10"-' gram sevens). 



n Repeller mode number. The number of cycles drift is n -{- -} for "optimum 



drift". 



p Reduced power (9.5). 



r Radius of grid wire, radius of tubes forming gap. 



t Time, seconds. 



Uf, D-C velocity of electrons. 



