title: Double-T armature
text: # Double-T armature
  
  Double-T armature - Shape of armature used in some motors and generators. Two 'T' shapes extending from axis.
  
  Its use in early Siemens dynamos caused a pulsing variable DC output which was improved upon by the Gramme dynamo.
  
  Another improvement is the three-pole armature ('triple-T' armature) as in this image :
  
  