[Elecraft] SWR Readings:Differences

[pastormg2 at verizon.net]

Good Evening,
This is Mark Griffin, KB3Z and I have some questions regarding the SWR readings I get at my tower versus what I get on my K3. I will give the SWR readings that I got at my tower for a 40 meter rotatable dipole at 55 feet.

Tower:

7000  2.2
7025  1.8
7050  1.5
7075  1.3
7100  1.0
7125  1.1
7150  1.3
7175  1.6
7200  2.0
7225  2.2

K3 Readings:

7000  3.5

7025  3.2

7050  2.9

7075  2.6

7100  2.4

7125  2.3

7150  2.4

7175  2.5

7200  2.6
7225  2.9

What would cause such a big difference. The cable run from my antenna switch on the tower to my K3 is only an additional 75 feet. I am using RG-213 cable. Is there anyway that I can test the SWR reading that my K3 is giving me?

Mark Griffin, KB3Z