According to from this circuit 12Vdc to 9V DC converter step down voltage by LM317T give current a little go to. We come to see the way enhances current better follow circuit picture enhance Transister TIP2955 or MJ2955 down go to help give current increase follow the circuit has can to enhance the trend is 5A 9V
After dozens of emails I have included the above circuit. The parts with the red ‘X’ are added and act to boost the amperage. The NTE393 transistor can handle 25A with a sufficient coolrib.
Other power transistors, such as the TIP2955, or similar can be used also. Read Source: http://www.uoguelph.ca/~antoon/circ/ps-lm317.html