Thanks, Morgan! That's very interesting.
Even at 100W using MFSK32, I've noticed that relaying an entire AmRRON AIB can cause my SWR to creep up near the end of the ~10 to 15 minute transmit. I suspected that it must be due to something heating up. At first I thought it might be the lightweight 1:1 Guanella choke that I made and put up on my 80m OCFD pole between the feed coax and the existing 4:1 Ruthroff balun, but perhaps it's my LDG AT-1000ProII, even though it is rated for 400W digital, which is much more than the 100W digital my IC-7100 puts out.
The other strange thing is the power meter on my 7100 LCD indicates that it starts to roll back power near the end too, but the 1000ProII LED meter, set for 100W scale, indicates no power reduction.
After a very brief cool-down, the normal SWR returns (down around 1.1:1 on both SWR meters). Maybe I'll use my VNA V2+4 to check the SWR at the coax input to my 1000ProII before and after a lengthy relay sometime. I'm not very motivated to go up on the snow-covered roof in winter weather to drop the antenna down and inspect the Guanella choke unless it fails! I'll try reducing power next time and see what happens, but many net participants are in the skip zone and power matters too.
73
Cal? AD8Q
