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I fired up my 15W Champ build yesterday. I went carefully through the first-time-turning-it-on steps and made it to the end where I was hoping to hear the white noise hiss of an amp, but I hear nothing. Whomp-whomp.

I'm attaching some pictures. I can provide more as needed. I'm looking for guidance on where to start. Not that it's a big amp/circuit, but I don't have a ton of spare time, which is how it took me 2-3 months to get to where I was finally turning this thing on.

Note that I have an 8ohm speaker. I want to make sure I am using the correct lead for the 8 ohm. I got a little confused between the 5w and 15w instructions.

Thanks!

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Are the heater filaments glowing on all three of the vacuum tubes? Do you have a multimeter and know how to safely take high DC voltage readings with it?

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

All 3 tubes are glowing up for me.

I do have a meter (multiple multimeters, in fact) and I can read voltages.

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With the amp turned on, take DC voltage readings on the following tube socket pin locations and report your results here.

12AX7: pins 1 and 6
6L6: pin 3
5Y3: pin 8

For the 15W output transformer, you should have its blue wire connected to the turret at the positive side of the first (16uf) filter cap, which is also where the wire from pin 8 of the 5Y3 socket connects. The red output transformer wire should connect to pin 3 of the 6L6 socket. From your photos, it's not clear to me where your blue OT wire connects. The brown OT wire should be taped off or capped.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

My blue wire is not connected. I was confused by the instructions here:

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More pics

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Okay, that's your problem. The input side of your OT isn't fully connected. The blue wire needs to go to the turret where the red wire from pin 8 of the 5Y3 socket connects. The brown wire should be capped or folded back on itself and taped off so that it can't short against anything.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

And we have output! I guess it help to connect all the wires, huh?

I am getting some sputtering happening, especially in lower notes, like a big open E. This isn't warm tube break up. I saw some sparking at pin 2 of the socket of the 6L6. I'm going to let it cool off and then re-seat the tube. Any other insights on what to look for are always appreciated.

You probably should check your wiring against the diagram, too. Bad things happen when something is wrong. Recently built my first amp, too.


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_________________
Pedal building is like the opposite of sex. All the fun stuff happens before you get in the box.

Yeah, these amp circuits are picky about that kind of thing.


I'd suggest reflowing the solder joints on ALL the pins of the 6L6 socket.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

I flowed the terminals on the 6L6 socket and was still having the sputtering issue. While testing it, there was the sparking at the sockets still happening. I was trying to determine exactly which pins were sparking, the sound cut, and there was a steady hum. I pulled the 6L6 and found scorching on pin 3. There was sparking on the rectifier tube socket also on pin 8. These are both on one side of the output transformer. I don't suspect the transformer is the issue. I'm leaning toward the pins in the sockets, not making a good connection. I have a couple of 8 pin sockets around that I will swap in.
Further insight is appreciated!

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I finally replaced the sockets today. I went through the process of starting it up, and when I got to testing the 6L6, sparking started happening on either pin 2 or 3 of the socket. Then the fuse blew.
I'm wondering if the problem is the tube or the output transformer. I'm hoping tube!
Thoughts anyone? Troubleshooting steps?

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Try a different 6L6.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Finally made it to Gui-target today to grab some tubes. The new 6L6 did not fix the issue. Not sure where to go from here.

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Probably time to take it to a qualified amp repair tech.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Bummer. This project is getting expensive. So it goes!

A positive is that my amp guy is a friend, and I haven't seen him in a while. I have some other tune-up work I could have him do.

A negative is he will likely roast me for my mistakes. Part of the price, I guess.

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But the plus side is that you will probably get some good advice/information for the future. Sorry that we were unable to solve the problem for you here. But when the more obvious things don't work, it's time to get an expert pair of eyes & hands on the problem. Best of luck to you!

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2