XOR gate without power supply

In electronics, are more frequently circuits required, in which a switching operation is triggered when a signal is present at one of the two input lines, but not when none or when there is one on both lines. A logic circuit that does just that, is called an exclusive OR gate, XOR for short.

The circuit shown does not require supply voltage. The output signal is obtained either via the 22kΩ resistor from input 1 or via the diode path of the upper transistor from input 2.