Power Transformer issue in Tube Amp

RogueEagle91RogueEagle91 Regular
edited October 2011 in Life
I've been attempting to build myself a tube amp/cab for the past month or so now.
I've finished the cab, works just fine.
I'm running into a rather large problem with my transformer connections on the amp itself.

Everything I've researched suggests using a 330-0-330 transformer. DC.
Well, i've got that.
Problem is, my tubes aren't lighting up (even though the test fine) and my transformer starts to warm up after a minute or two.
As I've had more than one transformer burn out while working on projects, I disconnect the power supply before any damage is done.
I've tested the transformers I've got each time this happens, and they all ready fully functional.

Here's a link to the schematic I'm using.

My transformer(s) are color coded 2 black wires, 2 red, 2 green, 1 red/yellow.
As far as I've found, the 2 black are the primary, reds are secondary, r/y is CT, and the 2 green are for heaters.
All wires come out of one side, so there's no definitive "this is your primary, this is your secondary".
This is just what i've found so far.

One possibility is the On/Off switch I'm using isn't rated correctly.
What would you guys use?
The input to the switch should run around 330VDC, 2A max.
The other is my color coding is wrong.
If you guys can tell that it is wrong, what's the correct setup?

To the best of my knowledge, everything else on the amp is wired correctly.
This seems like the only thing keeping me from having it up and running.
Any help would be greatly appreciated.
Thanks.

btw, here are some pics of the cab/amp case:
307345_10150336677414170_505344169_7866554_866340956_n.jpg

2011-09-29171223.jpg

Comments

  • chippychippy <b style="color:pink;">Global Moderator</b>
    edited October 2011
    From your schematic, the transformer has 3 secondary windings. One of which is center tapped to ground. In your description you only mention two windings, the red's with a ct and the greens. You have a secondary missing it seems.
  • RogueEagle91RogueEagle91 Regular
    edited October 2011
    That would certainly make more sense...
    Now that things are clicking, does my wall outlet connection go through the switch and fuse and THEN pass on to the transformer?
    Also, looking at standard Fender transformers, I have a feeling I may have just plain ordered the wrong transformer rather than having "missing" secondaries on the one I've got.
    Shit.
    Well, thanks.
    Such a short post, yet so much has become clear.
  • Darth BeaverDarth Beaver Meine Ehre heißt Treue
    edited October 2011
    Wow chippy, I am impressed you have a wide range of knowledge sir.
  • DaktologistDaktologist Global Moderator
    edited October 2011
    You say your heaters aren't coming on. I would check for voltage across them first, looking at the schematic there should be 6.3 v across them. Next check continuity from transformer to each heater terminal, There could be a loose connection somewhere.

    But as chippy said and from what I am seeing there is a heater winding for the 5Y3 rectifier tube, the HT secondary and a 6.3 V supply for the heaters on the 6SL7 and 6V6 tubes. One thing i am interested in is whether or not your rectifier tube heater is on.
  • RogueEagle91RogueEagle91 Regular
    edited October 2011
    My primary issue is my transformer isn't hooked into the rest of the circuit (tubes, caps, resistors included) properly.
    From there, I've seen methods on artificial CT's to hopefully work around the secondaries issue.
    Not ideal, but I'd like to see if the rest of the setup works before buying another power transformer.
    We'll see what happens with it tomorrow.
    I'll update then.
    Thanks, guys.
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