QRP MOD: One of the problems experienced by reducing the low power setting to 5 watts is that the AT50 tuner requires 10 watts to operate. A unique solution is to reduce the medium power setting (50 watts) to 5 watts by adjusting pot VR16. This allows the tuner to tune at the 10 watt low power setting. After tuning, go to the medium power setting (now 5 watts) to operate QRP.