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Lightning L6 matching

I inherited this antenna setup from my uncle. Made a lot of contacts UK, Australia just a few. But this antenna setup has been a rabbit hole ever sense I got it. I had several lengths of coax. Depending on how I hook up the jumpers between radio,amp,meter and my multi point antenna connection my meter would change from 1.5 to a 2.75or some other random reading. So I seen where people would use 1/4 wave jumpers so I bought some rg400 and made several of 1/4 wave jumpers. Now my meter shows a flat 1-1 SWR across all the CB frequencies. So how can you trust any reading on a shack meter? Everything I have read and studied says when that happens it’s always an antenna mismatch. This leaves me with the only way to make sure it’s all right is to use an analyzer at the feed points. This got me over thinking the whole system. Just like what yall mentioned in previous post. I know this forum has a lot of experience operators and technicians. If I connect my analyzer at the switch in the shack it shows 35 ohm. I know that is a system reading and not antenna alone. Over all it seems to work ok but those SWR readings are always eating at me.
 
The SWR meter in the shack is probably telling the truth. Having an impedance match and having the system balanced are two different things.

When you change coax length and the SWR changes, it suggests the antenna is unbalanced and the outer shield of the coax is acting as part of the antenna. Changing the coax length changes the impedance looking down the outer shield, just like changing the length of a whip antenna changes its feed point impedance. Think of it like two antennas connected in parallel, the beam being one, and the outer surface of the coax leading back to the shack the other. If the beam's feed point impedance and this common-mode impedance looking down the shield combines to give 50ohm, you have a perfect SWR.

To prevent the coax length from affecting SWR, you would need some type of balun at the feed points. That applies to the analyzer as well. Since the system has proven itself to be unbalanced, you can expect the coax running down to your analyzer to also act like an antenna and lead to improper readings.
 
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