Announcement

Collapse
No announcement yet.

Novice 5e3 Build Pops fuse & has low hum/no output

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    is this the layout you were using??
    Attached Files

    Comment


    • #17
      Yes, that is the exact diagram I was using, which ones are the preamp electrolytic caps? I am sitting in class right now, I should be back at my dorm in a few hours though and I will check the preamp tube pins 4, 5, and 9 along with the preamp electrolytic caps, if you can tell me which ones the are ^.^

      Comment


      • #18
        Nevermind, i see exactly which ones are the electrolytic caps. I also noticed that I missed the wires going from v4 to v3 on pins 2 & 7, So I will have to take care of that whenever I get back.

        Comment


        • #19
          Okay, so I got the amp to "work". I reversed the direction of the preamp electrolytic caps and attached the jumpers on pins 2&7 between the 6v6's that I forgot. And now with the amp working and creating sound, a new problem has arisen; the volume controls dont seem to do shit, and actually the amp has a cranked tweed tone constantly. Whenever I hit a chord hard, the amps volume actually decreases, kind of a reverse volume swell effect. wtf? any ideas now? lol

          Comment


          • #20
            Mission 5e3 Build - Crackle and voume swell?

            Okay, so here is the latest pic of my chassis. so far so good, im hoping...
            along with this new problem, input 2 of the bright channel doesnt work even though i get a clean connection off the jack to the 68k resistors (multimeter tested)... defective jack maybe? it looks fine.

            Comment


            • #21
              LOL I just accidentally cracked one of my 6v6's while it was out of my amp. No more work until tomorrow. I hope someone in town has tubes in stock. well, that gave me a laugh i needed after much frustration.
              I did rewire all 4 inputs, added a missing ground jumper from one of the volume knobs to an input ground, and I'll just have to see what that did to help.

              Comment


              • #22
                Originally posted by Apocrathia View Post
                LOL I just accidentally cracked one of my 6v6's while it was out of my amp. No more work until tomorrow. I hope someone in town has tubes in stock. well, that gave me a laugh i needed after much frustration.
                I did rewire all 4 inputs, added a missing ground jumper from one of the volume knobs to an input ground, and I'll just have to see what that did to help.
                There are no defective jacks... trust me on this... 99% of all the small problems novice builders have is simple wiring errors and very very rarely a defective part.
                From your pictures it is hard to tell but I think the input jacks might be wired wrong.
                Look carefully at the included input jack artwork that came with the kit in the large documents envelope.
                Those switching input jacks seem to baffle new builders.
                Look at the attached photo here (down below) and make sure they are wired this way...

                An ungrounded volume pot (especially if it is the normal channel volume pot in this layout) means the amp will be running wide open, full volume with no attenuation.

                Please make sure your three unused high voltage secondary wires are cut clean with no bare wiring showing and are not all bundled together in one piece of shrink tubing.
                I can't see where you connected the power cord's neutral whit wire to the PTs neutral wire.
                Also make sure your two 220K grid load resistors for the 6V6s are grounded at their junction.

                All the power tubes are "preselected" and are middle ranged as far as their natural resting idle current wants.
                For a quick test you can run that amp on one power tube for a couple mins... I know it sounds bad and will be hummy but you'll be able to tell if you are making progress.

                Also, the 5Y3GT is a NOS one but I always check them when I buy them and give them a 10min burn in to be sure I didn't get stuck with a dud.

                I think you are getting very close to being all figured out.
                Attached Files
                Last edited by Bruce / Mission Amps; 06-13-2008, 09:55 AM. Reason: added photo
                Bruce

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

                Comment


                • #23
                  The solder joints look cold & unreliable to me. Once you get your parts corrected I would reflow all the joints & make sure they are done properly before adding power again.

                  Sean

                  Comment


                  • #24
                    Here are the two pics I rewired my input jacks after.



                    There was a ground missing on one of my volume pots which probably had something to do with the failtone I was getting.
                    As far as solder joint go, I'm going to have to suck off half of the joints and redo them, I know. I tried to get the most of them as best as I could, but a few of them definitely need to be redone. I will tackle that later today.
                    Thanks thus far for all of your help. I have to get to class in a few seconds, but I will be going and buying tubes later today and I will get back to everyone with the results.

                    Comment


                    • #25
                      Originally posted by Bruce / Mission Amps View Post
                      For a quick test you can run that amp on one power tube for a couple mins... I know it sounds bad and will be hummy but you'll be able to tell if you are making progress.
                      I will have to try this when I get back. I was afraid to see what the out come of running the amp with 1 power tube would be. But then again it is a class A circuit and not A/B, so I suppose it wouldnt hurt it too much as long as it wasnt done for more than say 5 minutes, if even that.

                      Comment


                      • #26
                        w00t!

                        Just got back from my local music store and installed a new matched pair of EH6V6GT's just like i got from bruce (saving the other from the original set as a backup), and everything is WORKING!!!! 0-hum and the tone is awesome! (no tubes running too hot, I am really glad I didn't waste the money to send it back to be fixed (No offense bruce, lol.) and I did it myself, really helped me learn more about this amp. I will post pics later on in a different thread of my new setup.
                        Thanks to everyone who put in their advice and 2¢. and thanks to Bruce for kicking ass.
                        It's pretty cool/odd that this amp was finished on Friday the 13th, lol...

                        Comment

                        Working...
                        X