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

The Christiansen "DG" 300B Amplifier Build Thread

2 3 4 5 6 7 8 9 10 11
  1. sceleratus
    This post has been deleted because it contained the intellectual property of Neurochrome.
  2. PinkLed
    Excellent! Thanks for all the help by the way. [​IMG] Adding this thread to my favorites, really looking forward to seeing it finished. 
  3. HK_sends
    -HK sends
  4. OldSkool

    Ditto! This should be interesting... [​IMG]
  5. nelamvr6
    Looking forward to a very interesting build.  Good luck! [​IMG]
  6. HK_sends
  7. rb2013 Contributor
    Really nice- good luck!
  8. sceleratus
    Today I finished ordering all the components for the Damn Fine 300B with the exception of the 300B and 6N6P valves.  There are close to 150 components.  The enclosure will be custom made and it is in the design stage.
    I have created a Dropbox folder to put all the schematics, BOMs, Photos, and Specs.  I will update the post as I add material.  Presently there are:
    ·      300B Schematic parts BOMs and Photos
    ·      21st Century Maida Regulator Schematic, parts BOM, and photo
    ·      6.3V and 5V Filament regulator Schematic, parts BOM and photo
    ·      1950 Western Electric 300B valve specification
    ·      Christensen Damn Good 300B Amplifier internal and external photos
    ·      List of expenses.
    I will close with a photo of the interior.
  9. sceleratus
    I finished the 21st Century Maida High Voltage Regulator while waiting for the 300B boards and components to arrive. I thought I’d show some of my soldering, I rate it ok, and provide some great soldering resources for those how don’t think they can solder.
    First off, if I can solder, you can solder.  Despite persistent hand tremors I got it done.  First watch the Dave Jones, EEVBLOG, 3-part video on Youtube.  They are a bit long but well worthwhile esp. if you want to solder surface mount components.  Dave has even more advanced videos as well.  Who knows, you might want to hot-rod your Lyr some day.
    Part 1 is about The Right Gear and Solder.  This is where I learned about 0.38mm 5 core solder. That alone made it worth watching.  I also picked up a Hakko FX-888 Solder station.  This is a can’t miss tool.  Heats up quick and amazing control and tip cleaning.  An articulated desk, arm magnifier and a small Panavise is also essential.  There is also great information on solder wick and solder suckers to correct your mistakes or remove components.  I was familiar with solder suckers but did not know about solder wick....Yes this is basic.
    Part 2 is basic thru-hole component soldering.  I picked up more things I didn’t know.   Prior to this, when I had to solder something, it was very hit and miss.  Cold joints.
    Part 3 is soldering SMD components.  I never believed I could solder a component that is 1.18mm wide.  
    Same for LM22673 Ti switching regulators.
      They have 8 feet very close together.  Simply watch Dave’s video and you can do it.  Some of my work isn’t the prettiest but I had no solder bridges.  Dave shows you how to fix them anyway.  
    Here’s the finished product (less heat sink):
    Filament board.  Don't laugh,  it works..  The black spots are shadows off the shiny solder...[​IMG]
    Here's what's on the way:
  10. PinkLed
    Looks great! I remember when I tried to custom make a PCB with ferric chloride, copper clad, and a sharpie. It was fun but looked very sloppy. Btw I have the same caliper. That thing is a great tool. 
  11. sceleratus
    I'll be making a PCB for the valve tester.  It's a parallel project, but most of my attention is on the 300B.   There are some new etching techniques that appear to be better than ferric chloride.  The name of the process escapes me now.
    I'm using DipTrace to create the schematic (for the tester).  It produces the board trace from the schematic automatically.  I don't know that much about the circuits so I'm re-creating a few in LTspice to simulate and try to understand their function.  Again, this is more like a kit project.
    I could not live without a set of calipers.  I have an inexpensive set that has a 1/64th fraction table.  I use those a lot.
  12. sceleratus
    I'm looking for wisdom and recommendations for 300B and 6N6P valves.
    If you have any experience with these I love to read about it.
  13. sceleratus
    I was not going to write about my plans for the enclosure but I can’t keep a secret.  I’m really stoked and I think it will look interesting.
    The enclosure will be wood, have an antique style, and be made from walnut, mahogany, or rosewood.  Think “Old Cigar Humidor”.  I have a good friend that has been making custom kitchen cabinets for 30 years.  
    I will plate the top panel, either nickel or copper.  For the controls I did some shopping on eBay …
  14. sceleratus
    Boards and components arrived today.  I inventoried all the components and started to work on the driver board.
    8 components mounted, 65 to go.
  15. Fearless1
    "Western Electric=holy grail of the 300B" according to my friend who has a Grant FidelityA535 amp.
2 3 4 5 6 7 8 9 10 11

Share This Page