1000W Tube Amplifier Interference Pattern of the MV-Rectifiers

The line frequency is 50Hz - when the signal frequency is turned to 25Hz, the pulsing load causes this interference pattern through the mv-rectifier tubes. In some way this visualises the 120 degrees phase angle.
The frequency counter is a HP 521 full tube device, the noise you hear, is caused by its fan. But you can also hear the load choke during low frequency interfernce.

Видео 1000W Tube Amplifier Interference Pattern of the MV-Rectifiers канала histelek