NAKD: My first ground up build

[Casey4s]

What you have done so far looks very neat and well thought out. Kudos to you Keep up the good work and keep your fans posted.

[Ostinato Rubato]

I really admire you builder types. I still gotta build my FF clone...

[Dickarms]

Wired up the power transformer today:

so much chassis, such a little board. looks awesome.

[_ej_]

Wired up the power transformer today:

so much chassis, such a little board. looks awesome.

I once built a JCM800 in a chassis smaller than the one I'm working with now. It was awful. Way to freakin' cramped. Decided I wanted room for this build

[SenatorClayDavis]

Question for you builders, the schematic calls for use of the 8ohm tap off the OT with an extension cab out. However I want to wire the 2 outputs for 8 and 16 ohm taps. How would I go about this?

The OT should have 3 seperate wires heading out, one for each of 4, 8 and 16 ohms. At least the Hammond OT's I've worked with have the three outs. So if you've got to speaker jacks, wire the 8 to one and the 16 to the other.

[_ej_]

Question for you builders, the schematic calls for use of the 8ohm tap off the OT with an extension cab out. However I want to wire the 2 outputs for 8 and 16 ohm taps. How would I go about this?

The OT should have 3 seperate wires heading out, one for each of 4, 8 and 16 ohms. At least the Hammond OT's I've worked with have the three outs. So if you've got to speaker jacks, wire the 8 to one and the 16 to the other.

Yeah, I know that much. But theres some additional stuff wired to the jack on the schematic. Do I just leave it wired to the 8ohm jack?

[Casey4s]

Question for you builders, the schematic calls for use of the 8ohm tap off the OT with an extension cab out. However I want to wire the 2 outputs for 8 and 16 ohm taps. How would I go about this?

The OT should have 3 seperate wires heading out, one for each of 4, 8 and 16 ohms. At least the Hammond OT's I've worked with have the three outs. So if you've got to speaker jacks, wire the 8 to one and the 16 to the other.

Yeah, I know that much. But theres some additional stuff wired to the jack on the schematic. Do I just leave it wired to the 8ohm jack?

No, the yellow 4 ohm out is not wired to the jack. You could use that instead or install a seperate 4 ohm jack or install a switch to select between the two. Unless you think you may use the 4 ohm tap I would just leave it capped off. The green wire at the jack marked "Y" goes to ground.

I do not see a 16ohm tap in the layout. Does your OT have one?

[_ej_]

Question for you builders, the schematic calls for use of the 8ohm tap off the OT with an extension cab out. However I want to wire the 2 outputs for 8 and 16 ohm taps. How would I go about this?

The OT should have 3 seperate wires heading out, one for each of 4, 8 and 16 ohms. At least the Hammond OT's I've worked with have the three outs. So if you've got to speaker jacks, wire the 8 to one and the 16 to the other.

Yeah, I know that much. But theres some additional stuff wired to the jack on the schematic. Do I just leave it wired to the 8ohm jack?

No, the yellow 4 ohm out is not wired to the jack. You could use that instead or install a seperate 4 ohm jack or install a switch to select between the two. Unless you think you may use the 4 ohm tap I would just leave it capped off. The green wire at the jack marked "Y" goes to ground.

I do not see a 16ohm tap in the layout. Does your OT have one?

Yeah, I know the 4 ohm gets capped and the green goes to ground. I was referring to the pink wire connected to the ext jack. Not sure what that is for.

I bought a different OT to use that does have a 16ohm tap. I want to wire one 8 and one 16 ohm jack, so I can use one or the other (i have no intention of trying to run an 8 and 16 ohm cab at the same time).

[SenatorClayDavis]

Since you'd never use more than one jack, what I'd be inclined to do would be to just use one jack and install a switch to go from 8 ohms to 16 ohms (i.e. connect the 8 and the 16 wires from the OT to the switch, and then the line from the switch goes to the jack where the green "8 ohm" wire is currently in that diagram. The switch could just go where the EXT jack is.

I don't know what that pink wire is either, but you'd just wire it directly to your main jack where that red one is now.

[Casey4s]

Since you'd never use more than one jack, what I'd be inclined to do would be to just use one jack and install a switch to go from 8 ohms to 16 ohms (i.e. connect the 8 and the 16 wires from the OT to the switch, and then the line from the switch goes to the jack where the green "8 ohm" wire is currently in that diagram. The switch could just go where the EXT jack is.

I don't know what that pink wire is either, but you'd just wire it directly to your main jack where that red one is now.

Yup, I agree with the Senator.

Do you have a schematic of this circuit?


EDIT:


I went to Triode but they don't offer a schematic of this on their site for some reason. But I did find this original Fender schematic at Hoffman's site.

http://www.el34world.com/charts/Schematics/files/fender/champ_vibro_aa764_schem.pdf


That PINK wire is part of your vibrato circuit and has to be terminated on the oputput jack as shown. If you are not going to use an extension jack then just move it to the jack you are using. It needs to be there for 8 or 16 ohm operation. If you look at the schamatic you can see it comes off of the cathode of side B of your first preamp tube.

.

[_ej_]

Progress

[Casey4s]

Very neat work so far.

[_ej_]

So I got the bulk of the wiring done today. All that's left is the tremolo circuit and some grounds

I stupidly drilled the chassis backwards so the board is a mirror of what it needs to be

Still workable though. I just need to get some more wire and finish 'er up

[Turtle]

Great job!!! Where is the kit from? I'd love to try to build an amp myself. Are the instructions fairly easy? Thanks