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Only a guess - is R1 connected to the input side of the regulator?
Try breaking the problem down into steps.
1. Remove the ATmega32, it will work at maximum voltage if it is removed so at least you can check the regulating side without damaging the chip.
2. Temporarily ground the adjust pin and check you get about 1.25V at its output pin, this will check it is regulating.
3. Temporarily connect (ATmega removed!) JP4 pin 1 to +5V and check that again you get a low voltage out.
4. Temporarily connect JP4 pin 2 to +5V and see if R3 allows you to adjust the output voltage.
5. Keep calm and let me know the results of these checks.
Brian.
Try breaking the problem down into steps.
1. Remove the ATmega32, it will work at maximum voltage if it is removed so at least you can check the regulating side without damaging the chip.
2. Temporarily ground the adjust pin and check you get about 1.25V at its output pin, this will check it is regulating.
3. Temporarily connect (ATmega removed!) JP4 pin 1 to +5V and check that again you get a low voltage out.
4. Temporarily connect JP4 pin 2 to +5V and see if R3 allows you to adjust the output voltage.
5. Keep calm and let me know the results of these checks.
Brian.