| Year | 1930 |
| Date | 08-May |
| Volume | 62 |
| Issue | 1,513 |
| Page | 443 |
| Category | Electrical |
| Part | |
| Title | Building Up a 250-watt Double-current Generator or Rotary Transformer |
| Author | A.H.Avery |
| Notes | Complete machine, double wound armature with 2 commutators, double-current generator or rotary transformer, field magnet body, end frames, armature core, commutators, material, winding data, bearings, brush holders, parts |