Triple Servo Tester

I'm currently building several walking robots, all powered by servos. The problem then arises in working out the extent of motion with each one and also the range of motion available. I have several dumb testers, but needed one that displayed the actual arduino servo position number, from 1-180. This means I can manually adjust and take down the values. An arduino, 3 pots, some pins an SPI OLED and a JST is required along with a cheap power converter to ensure that it all runs at 5v.
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