Pietro,
Sorry to have been away for a few days.? I looked at your pictures of the display and the SWR does seem a little high.? The radio cuts back on power when the SWR goes up to protect the finals.? In the photo the radio is making power.? Now, many people have reported that the output relay does seem to go intermittent from time to time.? I believe that is do to either dirty contacts on the relay or reduced input voltage that is preventing the relay to make the switch.? Just for myself, I know the contacts are somewhat self cleaning when the relay operates.? Since I have several memories programed, on HF, VHF and UHF, I programmed one memory to use the front antenna connector.? By switching between that memory and a normal memory using the rear antenna connector, I can exercise the relay several times rapidly.? As a reminder, Yaesu designed the radio so that the front connector is the normally closed contact of the relay.? To use the rear connectors, power is supplied to the relay coil.? AS this is the most often used output, Yaesu kind of missed the definition of "low power" since the radio uses more power for the rear connector than the front.
I had a unique situation on my radio in that in UHF, the SWR always showed a little higher than the VHF.? And it showed different that an outboard SWR meter.? So I went looking for an issue inside the radio.? What I found was a small cap that must have fallen into the radio during assembly in the UHF SWR circuitry.? All of the other parts were correct.? So I removed the cap, readjusted the SWR bridge and checked the software.? Now the internal SWR meter agrees with an external meter and I no longer have HSWR warnings.?? My previous 817 also suffered from the relay contact issue.
Good luck
?
Al Skierkiewicz
WB9UVJ
Al WB9UVJ