Fuse blew - did usual - removed all valves, left speakers in - blew again - found MR67 diode 5ohms either direction - got diagram forced out of Yarland - o/p and P.S, but didn't resemble P.S - 200 ohm res excluded and FW rect. not right diagram - no time to trace cct. - replaced MR67 and schottky diode, still blew fuse - need wizard to say - oh, that's OK, its just component x,y,z. - save my amp!\nAny ideas as to where to go next? I am not right up on valve Power supplies, and I can't figure the half schottky - only one side is connected.\nDave.