Sudden SWR spike

OK, the B100 antenna is junk, it uses the shielding of the feedline (coax) to be the other half of the antenna system and it causes all kinds of problems, especially with short runs of coax. You need at least 20 feet of coax for it to come close to what it is supposed to have. The antenna itself is a 1/8 wave antenna, the design isn't the greatest and it is limited in power handling, I've heard some short out at 20 watts.

In a proper setup, mobile or base, no matter how much power you add, the SWR will always stay the same. This tells me what I said before, there is a problem with the way this antenna design uses the shielding of the feedline (coax) to be part of the antenna system.

This is because there is feedback on the other half of the feedline from the antenna which messes ith the radio meter itself.

You running power or just a radio?

If it is just the radio and this is an external meter, that make sense but if you are using an internal meter, well that's why I don't trust radio meters other than to show me there is power.

That's because there is a serious problem with the antenna and feedline (coax).

I suggested a simple verticle dipole for 11 meters is easy to make (16 gauge hook-up wire) and could be used against the house from the second floor.