OTL Asylum

• RE: Help needed: OTL3 Front End Bias not reaching 85V - unlisted 09:16:43 01/31/15 (2)
  In Reply to: RE: Help needed: OTL3 Front End Bias not reaching 85V posted by rhinohifi714 on January 30, 2015 at 19:48:53

  Thank you!
  
  Tried swapping out the 6EJ7, but no luck. Tested all of the tubes on a tester and they test fine too. Think I found a resistor that has significantly drifted and ordered a replacement to try (right by the front-end bias test point, so that would fit with what I'm seeing). The caps appear to be fine and I'm a bit surprised given the amps age...guess driving ESL's are good for it. My OTL3 doesn't really match the schematics I have that well, so I need to try it to make certain that's the issue. I'll post what I find.
  
  Thanks again!
  

  ---

  • RE: Help needed: OTL3 Front End Bias not reaching 85V - unlisted 09:37:00 02/06/15 (1)
    In Reply to: RE: Help needed: OTL3 Front End Bias not reaching 85V posted by unlisted on January 31, 2015 at 09:16:43

    R37 wasn't it ... swell :(
    

    ---

    • RE: Help needed: OTL3 Front End Bias not reaching 85V - Banat 17:57:56 02/06/15 (0)
      In Reply to: RE: Help needed: OTL3 Front End Bias not reaching 85V posted by unlisted on February 06, 2015 at 09:37:00

      -Check for bad solder joints on all tubes sockets pins on underside of PCB board ,with special attention for Magnoval tube sockets pins dedicated for output power tubes and voltage regulator tubes , ( hope that original tube sockets are ceramic high quality types ) .
      -Also check few small electrolytic capacitors for correct values which are placed on the top of PCB , they want to dry up when work in hot surrounding as is by any OTL amp.
      -Check all resistors which are with mega-ohm values , and all others resistors with values above 220K , after long period of use those resistors sometime want to change(raise)the value .
      -And yes , before doing anything from above make sure that NO electricity is present inside of that OTL unit , with special attention on PSU electrolytic capacitors , since they want to keep the potentially shock hazard electrical charge for several days .
      
      Best Regards
      __
      
      "Art which does not have the appearance of art is true art."
      - Old Roman saying -
      
      

      ---

Post a Followup:

This post is made possible by the generous support of people like you and our sponsors:

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]

---

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

---