Announcement

Collapse
No announcement yet.

Experimenting a Solid state rectifier - Readings

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Experimenting a Solid state rectifier - Readings

    Hi guys,
    Today, I have installed a solid state rectifier, weber WY3GT to replace a NOS 5Y3GT.

    This is what happened, I toke some voltage readings with a tube and a tube rectifier ;

    Rectifier socket:
    Vacuum tube rectifier: Pin 2 and 3: 388v
    Solid state rectifier: Pin 2 and 3: 323V

    Power tubes:
    Vacuum tube rectifier: Pin 3 to 8: 383v
    Solid state rectifier: Pin 3 to 8: 303V

    Also, I checked the cathode current on power tubes in the probe:
    Vacuum tube rectifier: 37.5Ma
    Solid state rectifier: 30.5Ma

    I don't understand what is happening here. I though that solid state rectifiers would increase voltages not bring them lower?!

    In the end of the day I liked the way the amp behavior. I notice that the amp sounded cleaner with more dynamics.
    Thanks one more time for your support..

    Regards
    Last edited by tweed; 10-19-2009, 10:32 PM.

  • #2
    I believe typical ss diodes don't drop much voltage (about 0.7v per diode) for a common one. I have read the Weber WY3GT drops about 50v, maybe to help simulate sag??

    I plan on ordering a Weber to play with so I would be interested in hearing the answers to your questions. Also, I'm not understanding your last sentence, is the 5y3 or the WY3 cleaner?

    Thanks

    Comment


    • #3
      Originally posted by tweed View Post
      Hi guys,
      Today, I have installed a solid state rectifier, weber WY3GT to replace a NOS 5Y3GT.

      This is what happened, I toke some voltage readings with a tube and a tube rectifier ;

      Rectifier socket:
      Vacuum tube rectifier: Pin 2 and 3: 388v
      Solid state rectifier: Pin 2 and 3: 323V

      Power tubes:
      Vacuum tube rectifier: Pin 3 to 8: 383v
      Solid state rectifier: Pin 3 to 8: 303V

      Also, I checked the cathode current on power tubes in the probe:
      Vacuum tube rectifier: 37.5Ma
      Solid state rectifier: 30.5Ma

      I don't understand what is happening here. I though that solid state rectifiers would increase voltages not bring them lower?!

      In the end of the day I liked the way the amp behavior. I notice that the amp sounded cleaner with more dynamics.
      Thanks one more time for your support..

      Regards
      Hmmm... you have something wrong there chief.
      Maybe you just misquoted.
      Only even numbered lugs are used with 5Y3s, 5V4s, 5U4s, 5R4s, 5AR4s, GZ34s and probably others I can't think of... 2, 4, 6 and 8.
      2 and 8 are the heaters and cathode, while 4 and 6 are the high voltage anodes.
      Many years ago, I did quite a bit of the beta testing sag resistor tweaking adjustments for Weber on and inside those copper cap rectifiers.
      They were/are pretty close to vacuum tube parameters when used within normal current load levels.
      The only problem I ever really had was that at very high current levels they drop more voltage and they get hotter then a $2.00 pistol on Saturday night in a back alley off Bourbon Street, LA.
      Also, if the solder sags out and a resistor or diode lead touches the copper somehow... pow... B+ all over the place on the outside of your copper cap.
      Bruce

      Mission Amps
      Denver, CO. 80022
      www.missionamps.com
      303-955-2412

      Comment


      • #4
        Yep those copper caps have 'sag resistor(s)' in them to drop more voltage. Maybe they put the wrong value resistor in that particular one (perhaps)??
        Building a better world (one tube amp at a time)

        "I have never had to invoke a formula to fight oscillation in a guitar amp."- Enzo

        Comment

        Working...
        X