This small realization, based on one of the most common IC MAX232 is designed to create a small and convenient TTL to RS232 and vice versa convertor.
All you need is 4 caps, one IC and 2 connectors. If you want to add a small regulator on the board (already foreseen on the PCB) you just need to add a 78L05 regulator and a cap.
If you do not need to regulate the power supply, you can just replace the 78L05 by a strap (pin1 to pin 3) and drop the 78L05, C1 and C2.
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