In this paper, we implement an algorithm that automatically switches the total modulation orders in a field pick-up unit (FPU) for mobile live program productions and evaluate its performance through laboratory and field experiments. We are conducting R&D on high-capacity FPUs for mobile live 4K/8K program productions, such as live broadcasting for road racing. Using adaptive transmission control, we aim for stable transmission in poor propagation environments and high-speed transmission in good ones. The switching algorithm is expected to expand the variable range of throughput. We implemented the algorithm in a prototype and evaluated the algorithm's operation through laboratory and field experiments.As a result, it was confirmed that the variable range of throughput, 2.79 times with the conventional method, was expanded to 3.40 times, and the stable transmission area was expanded.