I have built this circuit with LM317T and LM337T:
The problem is the output voltage will drop under load when i have C3 and D7 connected. Unloaded the voltage over R1 is 1.1 volts, and if i connect a load (LED and 1k resistor) it drops to 0.9 volts. Without C3 and D7 it works and the voltage over R1 is 2.2 volts. Same problem on the bottom side.
The problem is the output voltage will drop under load when i have C3 and D7 connected. Unloaded the voltage over R1 is 1.1 volts, and if i connect a load (LED and 1k resistor) it drops to 0.9 volts. Without C3 and D7 it works and the voltage over R1 is 2.2 volts. Same problem on the bottom side.