I have a beautiful old frequency meter from a power station, a "System Frahm" type panel based on vibrating reeds. It has two rows with 21 reeds in each, each going from appx. 45 Hz to 55 Hz. It says that it accepts 110 volts.
I want to be able to provoke the instrument to indicate frequencies of my choice, between 45 and 55 Hz. If possible, different frequencies on the two rows, but it's not mandatory.
I have access to a VFD, the Delta VFD004S21A 220V 1-Phase model. I know it can generate 3 phase power at the frequency and voltage that I need, but will it be able to run without driving a motor, or any other load? Would it work if I added a small 3 phase motor? Would I be better off with some kind of audio power amp + step-up transformer solution?