| Year | 1938 |
| Date | 03-Mar |
| Volume | 78 |
| Issue | 1,921 |
| Page | 206 |
| Category | Electrical |
| Part | |
| Title | Reducing the Noise from Electromotors |
| Author | A.H.Avery |
| Notes | Magnetic humming (from flux disturbance of armature teeth, electrical faults, skewing armature slots, drop testing the condition of the coils, foundation troubles, silent mounting on eleastic foundation, radio interference (suppressing by condensers) |