Coax Cable Physical/Electrical Length

This worksheet calculates wavelength (W.L.), half wavelength and quarter wavelength of coaxial cable based on the velocity factor of said cable at a frequency of interest. If the dielectric constant (er)of the cable is know rather than the velocity factor (vf), that parameter may be entered instead.

Remember that manufacturers published values for velocity factor are "nominal" and vary in "real life" from reality. It is not uncommon, for example, to see the velocity factor vary from one end of a 500' reel of coax to the other. Part of the problem is the inability of coax spooling machines to maintain the same tension on the cable when the reel is just being started (small winding radius) to when it is finished (large winding radius).

Do you know the velocity factor (vf) of the coaxial cable?   YES     NO

If "YES" enter the cable velocity factor vf:  
If "NO" enter the dielectric constant er:      

Select the units of the fequency of interest:  MHz     GHz
Enter the frequency of interest:                   
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