Announcement

Collapse
No announcement yet.

Zener diode question

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

  • Zener diode question

    I have a 60vt 50watt Do5 (anode to case) Zener diode and I want to drop the overall voltage 60 volts. I have a Fender DeVille PT that is bridge rectified and I hooked the stud end to the ground of the bridge rectifier and it only dropped 4 volts. Do I hook the zener to the + side after the rectifier? Any help please! Thank you.

  • #2
    What is the output voltage of the supply that you are trying to clamp with the zener? What is the ripple voltage? Do you have the zener before or after the filter caps? If you put the zener in backwards it will just be a foreward biased silicon diode to ground with a .6v clamp and short our your supply. I suspect that you are trying to clamp a poorly filtered and regulated supply so a meter reading will be ambigous. Use a scope if you can and put put the zener after the filter caps. Post a schematic and indicate what you are trying to do and it will be infinitely easier to help you.

    Comment


    • #3
      Hello, thanks for the reply. This PT gives me 470vts on the power tubes and I want to drop it 60 volts. I have a NTE 5278A that is 60vts and 50 watts but I get no drop with the stud attached to the center tap. I also have a Weber Z-Dropper that is 30vts and 25 watts. The Weber gives no wiring instructions and it is very difficult to contact him. I assumed you attached the center tap to the stud and the other end is bolted to the chassis. However there is no voltage drop. Am I supposed to attach it after the rectifier instead of attaching it to the center tap? I would go ahead and try this way but will I blow something up? Thanks for any help

      Comment


      • #4
        You want to connect cathode to ground. Plenty of threads on this subject, do a search.
        WARNING! Musical Instrument amplifiers contain lethal voltages and can retain them even when unplugged. Refer service to qualified personnel.
        REMEMBER: Everybody knows that smokin' ain't allowed in school !

        Comment


        • #5
          My NTE says D05 (anode to case). I must have ordered the wrong one. I need a cathode to case. But if the Weber is also anode to case is it meant to be attached to the rectifier? It sure doesn't work attached to the CT. Thanks.

          Comment


          • #6
            I use a Weber "Browner" to drop the AC to my old amps and keep the heaters at 6.3volts...

            Comment


            • #7
              I isolated the casing and reversed the wires. Now it works.

              Comment


              • #8
                Zener suffix

                You need that same Zener with the AK suffix.

                Comment


                • #9
                  I found one at a local electronics shop with the AK. It works great. Thanks!

                  Comment

                  Working...
                  X