Help please - EL34 Red plate on 1 tube

Discussion in 'The Workbench' started by Deepstone, Aug 12, 2012.

  1. plexifier

    plexifier Active Member

    Joined:
    Aug 13, 2011
    Messages:
    515
    Likes Received:
    186
    Location:
    Iowa
    Good call. We may not have the correct schem yet.

    Ricky: Got any schems that match the pictures?

    (Also note the "paper caps" that look like resistors, just to add to any confusion here. ;) )

    Deepstone:
    Which power tube red-plates (V4 with green wire to pin 5, or V5 with orange wire)? Did you try swapping the power tubes (V4 to V5 and vice-versa)? Since you've had the same problem with two sets of tubes, it's probably in the same socket but let us know.

    It may help if you post some voltage readings from both power tube sockets if you're comfortable doing so. Remove the power tubes first, power on and exit standby. Post voltages for pins 3, 4, 5 and 6. All are DC and can be measured at your meter's highest DCV setting (the yellow "500"). Be careful and ask if you're not sure about anything.
     
  2. Deepstone

    Deepstone New Member

    Joined:
    Aug 1, 2012
    Messages:
    26
    Likes Received:
    2
    Location:
    California
    here is a link to a new pic with the circuit board number for rickylee...thanks

    click here
     
  3. mickeydg5

    mickeydg5 Well-Known Member VIP Member

    Joined:
    Sep 30, 2011
    Messages:
    21,227
    Likes Received:
    8,907
    Location:
    US of A
    That is a "C" board and I have not been able fo find a schematic that matches the board numbering.
     
  4. RickyLee

    RickyLee Well-Known Member VIP Member

    Joined:
    May 22, 2010
    Messages:
    9,341
    Likes Received:
    2,816
    Location:
    Riverside CA U.S.A.
  5. Deepstone

    Deepstone New Member

    Joined:
    Aug 1, 2012
    Messages:
    26
    Likes Received:
    2
    Location:
    California
    Finally got the amp going tonight ..It was a bias resistor that had a crack that was hard to see...the one picture I had that showed the resistor jumpered on top of R48 was someones attempt at fixing it i guess? anyway put in a 220 resistor on R48 and it is working great now...thanks again for all the tips...Deepstone
     
  6. Deepstone

    Deepstone New Member

    Joined:
    Aug 1, 2012
    Messages:
    26
    Likes Received:
    2
    Location:
    California
    :slash:
     
  7. mickeydg5

    mickeydg5 Well-Known Member VIP Member

    Joined:
    Sep 30, 2011
    Messages:
    21,227
    Likes Received:
    8,907
    Location:
    US of A
    Have fun. :thumb:
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice