fet simply amp

very simple cheap fets ampli and  with good performance. i ll be glad to anyone will improve the circuit and  makes one side pcb. thanks

set the bias as about 3,1  volts on gate of irfp240. turn r9 from minimum resistance , then turn until 3,1 volts on gate fets-  you can use various devices in input  differential stage like bc 239, 2sc1845, or fets like 2n 7000- for q3 you can use 2sb649 or others.  the picture published is mounting  two output fets only. r2 is input sensitivity. i tested it until +60 -60 volts.