I have an FT817 that i have tested through a dummy load and a bird watt meter(50H slug). All bands are relatively around 5W of output power(4.9 - 5.1). On 80m I get 10W of power output on my cobra ultralight antenna. My EFHW vertical, I get 5W as well as my NVIS antenna. Perplexed as to why my Cobra antenna shows 10W and my other antennas show 5W when my FT817 only puts out 5W. I have tried my KX3 in this same manner and I do not have any issues of this sort. I am using an elecraft T1 tuner on my FT817. Thoughts?