5. 2. 1 Theoretical Treatment

For pulse counting, the form of the transmission line equation’ ‘ is

M)

2012 7Г b Z,

phase constant = 2 v f c ZQ,

resistivity of conductor material, in ohm-meters,

frequency, in cycles per second,

inner radius of outer conductor, in feet,

outer radius of inner conductor, in feet,

characteristic impedance of cable, in ohms,

capacitance, per foot, of cable,

length of cable, in feet,

voltage at sending end, and

voltage at receiving end.

Since we are interested in only the magnitude of the pulse, this can be written as

This equation is valid only if the cable is terminated in its characteristic impedance. To make it applicable for any termination, a term must be added to allow for the reflection factor. The complete equation, solved for I Vr! . is

where Z = termination impedance, in ohms.

GE АР-4 900