I am attempting to sell a bunch of radios from a friends estate & his Yaesu FT-900 will not receive or transmit. It comes on but does nothing else. I saw a post online about this same issue but it says something about a diode that fails that can cause this but they make no mention of what diode it is or where it's located in the radio? Does anyone here have any idea what diode they are refering to? Thanks much & 73 from Sunny & HOOOOT Florida.