QST
  Yesterday, I acquired a 2004 vintage Sharp microwave oven, from the "alley exchange", which was light (weightwise) enough that I thought it might contain a switching power supply.

  Upon examining the unit, I found that the incredible lightness was due to its construction with frame metal of soda can thickness, and that it contained a conventional transformer manufactured by one Digital Power Communications Co, Ltd.  

  There was an article in QEX about 10 years ago that discussed the use of these microwave oven transformers in plate power supplies.  It advised against using them in a conventional full wave bridge but, rather used them in an unorthodox half wave connection.

  Examining the transformer at hand, it appeared that the insulation was uniform over the full length of the secondary.

  I disconnected the "low side" secondary lead from the frame and hi-potted the secondary (also the primary just for science...) up to 4KV, referenced to the frame, with zero leakage.  

  This suggests that one of these transformers might be employed in a "normal" connection for a low voltage (2500V) KW input amplifier.   Or a pair of identical units in parallel for a 2KW input amp.   

  Caution, this suggestion MAY NOT hold true for other makers of this style of transformer.  

73 & Good afternoon,
   Marv WC6W  


P.S. -- The magnets from the magnetron assembly make great refrigerator magnets!





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