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It is possible (though not necessarily recommended) to replace the vacuum tube rectifiers in tube equipment with solid-state silicon diodes.



  so B+ will run higher unless series resistance or a regulator is included.
  Increased B+ might be desirable in a _few_ cases but will certainly place
  more stress on other components, particularly electrolytics, and may screw up bias points.
  This problem can be avoided by adding a time delay circuit.
  in reduced rectifier conduction angle, which can sneakily increase dissipation in the power transformer for a given B+ current.

General Precautions for Siliconizing (not specific to Hammonds)~:

  on the rest of the circuit, stick to a tube rectifier,
  or use guaranteed proprietary substitutes.
  dynamic impedance of the tube at the nominal operating current.
  and unplug all tubes.
  Then crank the volts up over a few hours to raise the B+ slowly from its old value to full.
  This forms up the electrolytics to better withstand the high voltage which will occur at switch-on.

In fact, there are so many caveats that I always advise keeping the tube rectifier unless there is an absolutely compelling reason to change it. Whatever you do, build it on the base salvaged from a dead tube, so that it just plugs in. Then, when you have pangs of guilt over depriving your machine of its natural complement of tubes, you can just swap back, without having hacked up the chassis!


  called  the "Copper Cap".
  It is supposed to mimic the I-V curve of the original tube, as well as have some
  sort of inrush current limiting (or slow turn-on).
  integral B+ tap (to power your Leslie 122 hookup kit.)


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