Hi all,
I used some basic calculations to determine the dielectric constant, velocity factor and characteristic impedance of the RG58 CU cable shown in the attached datasheet.
For determining the dielectric constant, the equation below was used, where C was taken as 100pF/m (listed in the datasheet), D as 3mm and d as 0.7818mm. With these values, I am getting a dielectric constant of 2.42 pF/m. Theoretically, for polyethylene this should be 2.3.
Also, the equation below was used to determine the velocity factor, which gives a result of 64%. Datasheet states 66%.
Using the dielectric constant found earlier, the characteristic impedance was also calculated and got 52ohms as a result. This should be 50ohms.
Since these are not practical results where some tolerances are expected, is there something which I am missing? Shouldn't these match with the info listed in the datasheet?
I used some basic calculations to determine the dielectric constant, velocity factor and characteristic impedance of the RG58 CU cable shown in the attached datasheet.
For determining the dielectric constant, the equation below was used, where C was taken as 100pF/m (listed in the datasheet), D as 3mm and d as 0.7818mm. With these values, I am getting a dielectric constant of 2.42 pF/m. Theoretically, for polyethylene this should be 2.3.
Also, the equation below was used to determine the velocity factor, which gives a result of 64%. Datasheet states 66%.
Using the dielectric constant found earlier, the characteristic impedance was also calculated and got 52ohms as a result. This should be 50ohms.
Since these are not practical results where some tolerances are expected, is there something which I am missing? Shouldn't these match with the info listed in the datasheet?
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