I fired up my Yaesu FT857d to take part in the RSGB's April 2018 2m UKAC Contest a couple of days ago to discover that the RF power output (Menu Option 75) was stuck at 50W and wouldn't change by rotating the VFO knob as it should.

Thankfully, despite being /P, I was in an area with good mobile coverage I had a quick google and although I found a few others who had experienced a few similar issues, there was only one viable suggestion for resolving the problem, which was to perform a reset. There are three variations of reset available on an FT857d detailed here. It was the FUNC + PWR one that worked for me, however it wasn't clear to me that this is a power-on reset, so the rig has to be off for it to work. There is a sort of 'confirmation beep' to indicate that the memory has been reset and you'll also notice that the VFO will probably have changed (in my case it reset to 7MHz).