Posted by GTCharlie (A) on April 06, 2007 at 21:02:02

In Reply to: AN K1, is too much if you can switch it? posted by beto1 on April 5, 2007 at 21:59:05:

it can be done, but twould be fairly complex. 2A3 filaments require less voltage, but higher current. 300B plate require higher voltage. your toggle switch would have to be between two power supply boxes.

• Re: AN K1, is too much if you can switch it? - AudioNoteKits 19:35:26 04/08/07 (3)
  In Reply to: Re: AN K1, is too much if you can switch it? posted by GTCharlie on April 6, 2007 at 21:02:02:

  Just to clarify the new Mains transformer that we use on the Kit1 is designed to support either a 300B or 2A3 triode . To make the switch requires changing the two wires going to the 5U4G from the 425 taps to the 325 taps - also we make a resistor change in the filament board so that the adjustable voltage regulator outputs 2.5V for 2A3 or 5V for 300B and the last change is the cathode resistors on the triode - we use 1K5 for the 2A3 and 1K8 for the 300B - So with about 10 minutes of soldering you can go between 2A3 and 300B!
  Brian Smith
  
  

  ---

  • Re: AN K1, is too much if you can switch it? - beto1 18:44:35 04/09/07 (2)
    In Reply to: Re: AN K1, is too much if you can switch it? posted by AudioNoteKits on April 8, 2007 at 19:35:26:

    Hi Brian,
    thanks for your info!.
    So, besides some resistors, for the old kit owners, need the new mains. Are this a Hammond special design for AN kits?
    Regards,
    Beto
    
    

    ---

    • Re: AN K1, is too much if you can switch it? - AudioNoteKits 18:50:19 04/09/07 (1)
      In Reply to: Re: AN K1, is too much if you can switch it? posted by beto1 on April 9, 2007 at 18:44:35:

      The new transformer is called the H301067 and is specially designed for AN kits for the 2A3 / 300b operation of the kit1 !
      Brian
      
      

      ---

      • Re: AN K1, is too much if you can switch it? - willleung 08:38:29 03/13/08 (0)
        In Reply to: Re: AN K1, is too much if you can switch it? posted by audionotekits on April 09, 2007 at 18:50:19

        Hi, is there any changes to the PSU resistors to the 5687 and 6SN7?
        
        

        ---

Post a Followup: