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  • #46
    I think it's a 10 ohm... And it's probably a good one, but it dosen't matter now...
    I cannot tell what the color bands, if any, are on that resistor in your picture. I'm sure it was wrong to start with.

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    • #47
      Originally posted by Meaux View Post
      I'll have you know you were the inspritation for the seperate On-Off Switch, and Volume Pot, from one of your posts I read awhile back... Thanks!...
      shsssh! That's a secret trick to reduce some of that "hum" so many SE Champ builders complain about... ;>)
      Also, if you decide to use a resistor and choke in series, you can use a smaller screen node filter cap by putting a little 8 to 10uF@450v cap in between the screen supply end of the choke and the start of the new resistor, followed by another 8uF to 10uF@450v cap at the end of the resistor ... then feed the screen, follwed by your normal preamp tube supply node with it's resistor and final filter cap, which also can be smallish.
      With the junction of the choke and the resistor, you get a chance to put another filter node in.... the positive side to this is that ... the little caps don't cost much and very little DC ripple will be at the end of the B+ rail when it comes time to hook it up to that 12AX7.
      Last edited by Bruce / Mission Amps; 11-19-2011, 11:45 PM.
      Bruce

      Mission Amps
      Denver, CO. 80022
      www.missionamps.com
      303-955-2412

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      • #48
        Originally posted by Bruce / Mission Amps View Post
        Also, if you decide to use a resistor and choke in series, you can use a smaller screen node filter cap by putting a little 8 to 10uF@450v cap in between the screen supply end of the choke and the start of the new resistor, followed by another 8uF to 10uF@450v cap at the end of the resistor ... then feed the screen, follwed by your normal preamp tube supply node with it's resistor and final filter cap, which also can be smallish.
        With the junction of the choke and the resistor, you get a chance to put another filter node in.... the positive side to this is that ... the little caps don't cost much and very little DC ripple will be at the end of the B+ rail when it comes time to hook it up to that 12AX7.
        Dang Bruce, you may as well be speaking Chinese to me... I went ahead and wired it exactly like a 5E1...

        Finished, and quiet as a church mouse... I'll swap out the 5Y3 for a GZ34 in a couple weeks, to see if there is any difference in sound... At '2' it's plenty loud for my use... and it dosen't dislocate my shoulder like the Pro-Reverb...





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        • #49
          That looks great! Congrats.
          Valvulados

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          • #50
            Here's what I meant.... forgive the kindergarten drawing with my mouse...... that is supposed to be a 2 watt resistor of about 2k7 ohms to 5k1 ohms
            Attached Files
            Bruce

            Mission Amps
            Denver, CO. 80022
            www.missionamps.com
            303-955-2412

            Comment


            • #51
              Any progress on your build? It sounds like everything was working fine, there is just some hum? How bad/lound is the hum? Since it is still present with the pre amp tubes pulled I would look closely at the lead dress (how you run your wires, solders, twisted AC lines, etc...). I was very surprised after poking around a few of my amps with chop sticks at how much this matters. One wire with AC on it that is run to close to a screen is enough to cause a considerable amount of hum.

              The PT that I used for my champ build had a center tap for the B+ but not for the heaters. I ended up adding a virtual center tap which quieted mine down considerably. I would try shortening and cleaning up all the wires you can coming off your power section including the long wires you have running to the fuse (which is outside of the chassis, not sure what you have going on there). You might also (if you have not yet) set your multimeter to continuity setting and test your grounds starting at the inputs. You should have continuity from the input ground all the way back to the main chassis ground and out to the ground on your 3 prong cord.

              Try to not get discouraged.... you're almost there.
              My Builds:
              5E3 Deluxe Build
              5F1 Champ Build
              6G15 Reverb Unit Build

              Comment


              • #52
                Originally posted by Bruce / Mission Amps View Post
                Here's what I meant.... forgive the kindergarten drawing with my mouse...... that is supposed to be a 2 watt resistor of about 2k7 ohms to 5k1 ohms
                Thanks Bruce, now it makes sense... I copied that for later use...

                Comment


                • #53
                  Originally posted by Wittgenstein View Post
                  Any progress on your build? It sounds like everything was working fine, there is just some hum? How bad/lound is the hum? Since it is still present with the pre amp tubes pulled I would look closely at the lead dress (how you run your wires, solders, twisted AC lines, etc...). I was very surprised after poking around a few of my amps with chop sticks at how much this matters. One wire with AC on it that is run to close to a screen is enough to cause a considerable amount of hum.

                  The PT that I used for my champ build had a center tap for the B+ but not for the heaters. I ended up adding a virtual center tap which quieted mine down considerably. I would try shortening and cleaning up all the wires you can coming off your power section including the long wires you have running to the fuse (which is outside of the chassis, not sure what you have going on there). You might also (if you have not yet) set your multimeter to continuity setting and test your grounds starting at the inputs. You should have continuity from the input ground all the way back to the main chassis ground and out to the ground on your 3 prong cord.

                  Try to not get discouraged.... you're almost there.
                  I'm finished and she's workin' fine... The only 'Humm' I have, is so low you have to try and listen for it, in a quiet room... Naturally, at 8-12 on the Volume, Humm increases... It is what it is... I'm Happy...

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                  • #54
                    Maybe there is a forum member in Alabama you can bribe with a six pack to take a look at your build?

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                    • #55
                      Originally posted by JHow View Post
                      Maybe there is a forum member in Alabama you can bribe with a six pack to take a look at your build?
                      Why would I want to do that? I just said I was finished, and I'm Happy... I'll drink the six pack myself, and I'm gonna start right now...

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                      • #56
                        Guzzle, guzzle.
                        Slurp, slurp.
                        Enjoy the amp (and the brewsky)

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                        • #57
                          Hola,

                          As a noob here, I gotta say this is great stuff, and has convinced me that this very circuit is gonna be the first for
                          me. I really appreciate the knowledge shared here for free. Even the layout from triode electronics, though I suppose
                          I could download that myself from their site, answers a bunch of noob questions about jack wiring and stuff that would
                          have been very tedious for me to puzzle out all by myself.

                          I have no illusions at this stage that without this kind of resource my first build could lead me down the same kind
                          of troublshooting BS that Meaux here has been dealing with. Hopefully I'll be able to post back here in the next week
                          or two with a success story. If not, maybe I'll at least come up with some new noob puzzles of my own.

                          Comment


                          • #58
                            The heck of it is, mine would have fired up on the first try if I had the correct resistor... Funny truth is, I wouldn't know shit about this dang amp without all the 'Troubleshootin', and I probably wouldn't be inchin' to do a bigger one...

                            Triple Check everything, unless you like 'TroubleShootin'...

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