Tweakers' Asylum

Posted by DMY on April 29, 2009 at 17:04:27

I have a power supply puts out 450v B+. It is a 5y3+CLCRC configuration. I am using it for a pre amp which only calls for 110v/40ma.
The first cap is a 0.5uf can not be smaller otherwise the choke will hum. The R is 8.5k/25w (7.5K+1k) and this big wire wound resistor runs very hot and warm up the whole chassis. Plus this big resistor would not be good sonically.

what is my other options if I have to use this power supply?

Many thanks for your help

• RE: need to drop high voltage PSU for pre amp - shermanr@prw.net 20:03:39 04/29/09 (2)
  In Reply to: RE: need to drop high voltage PSU for pre amp posted by DMY on April 29, 2009 at 17:04:27

  Why don't you regulate with a single OA2 and some resistors? You can also probably do a CLCLCLC to drop voltage in stages. Lot's of possibilities.
  
  

  ---

  • RE: need to drop high voltage PSU for pre amp - DMY 16:34:59 04/30/09 (1)
    In Reply to: RE: need to drop high voltage PSU for pre amp posted by shermanr@prw.net on April 29, 2009 at 20:03:39

    My problem is the heat from the resistor. If I were to use VR, the resistor still has to discipate lots of heat
    
    

    ---

    • RE: need to drop high voltage PSU for pre amp - shermanr@prw.net 07:35:33 05/04/09 (0)
      In Reply to: RE: need to drop high voltage PSU for pre amp posted by DMY on April 30, 2009 at 16:34:59

      I created a *.psu file of one possible solution.
      
      You can drop the necessary voltage using two chokes and two 10 watt resistors.
      
      Here are the values:
      
      Rectifier: 5Y3G
      C1 = 22 uF/600VDC
      L1 = 9H, 700 Ohms DCR
      C2 = 220 uF/450 VDC
      L2 = 9H, 700 Ohms DCR
      R1 = 3.3Kohm (10 watt)
      C3 = 220 uF/ 450 VDC
      R2 = 3.9 kohm (10 watt)
      
      I get 110 VDC @ 40 ma to the load. If you send me a mail I can send you the file from the PSU so you can load it.
      
      Thanks,
      Richard
      
      

      ---

Post a Followup:

---

[ Follow Ups ] [ Post Followup ] Thread: [ Display  Email  Next ] [ Tweakers' Asylum ]
[ Comment ] [ Copyright Warning! Click for Details ]

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2009, Audio Asylum, all rights reserved ] [ Go Green ] [ Take5 ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---