Fender 5e3p from Wurlitzer organ amp

[Zombie_stomp]

I drafted up a little bill of materials since I'm maybe not goin to find one prewritten. So for my one-channel version, here it is in the photo, just casually writing down what I see. There is one part I don't recognize on there labeled 'IN4007', anyone know what that is?

[Firestorm]

It's 1N4007. Silicon diode.

[Zombie_stomp]

Keeping track of everything while making way for new design.

[M Fowler]

If your building a Fender Tweed 5b6 circuit I would build it point to point no board.

https://tubeamparchive.com/viewtopic.ph ... highlight=

https://tubeamparchive.com/viewtopic.ph ... highlight=

[Zombie_stomp]

Question: are most OTs and PTs wires similarly color coded? I noticed more than a few common colored wires between my amp and the layout for the 5e3p design I'm using, and I can find the rest at the pins they're connected to. I'm just looking for the basic points and what they do. I'm sure I'll figure it out soon, just wondered.

[Zombie_stomp]

If your building a Fender Tweed 5b6 circuit I would build it point to point no board.

https://tubeamparchive.com/viewtopic.ph ... highlight=

https://tubeamparchive.com/viewtopic.ph ... highlight=

Yeah, I saw that build, it looks awesome! I guess what I have to figure out in my cartoon pea brain is how to lay it out and draw myself a new layout to work from instead of the board layout that already exists. I can see most of it in that first picture, which I took a copy of. I'm going to re-read that build thread and order some parts. And maybe try to draw a p2p wiring layout, deciding where to place everything in the chassis.

I took out the old can caps, and I've seen some modern clamp-in replacements, anyone know where to get any of those?

[Cliff Schecht]

Question: are most OTs and PTs wires similarly color coded? I noticed more than a few common colored wires between my amp and the layout for the 5e3p design I'm using, and I can find the rest at the pins they're connected to. I'm just looking for the basic points and what they do. I'm sure I'll figure it out soon, just wondered.

Yes but this is mostly from older magnetics, the newer stuff is not that consistent from one manufacturer to the next. From memory since I don't have any transformers in front of me...

Power transformer:
Black - Black ---> Primary side
Red - Red/stripe - Red ---> Secondary side HV with CT winding
Green - Green/stripe - Green ---> 6.3V CT winding
Yellow - Yellow ---> 5V non-CT winding

Sometimes a white wire is a bias tap from the HV secondary for fixed bias amps (ala Fender). Center taps are usually either a unique color or are the same color as the winding the CT is on with another color stripe. I always like to confirm that I have the center tap correct, not good to mix it up.

Output Transformer;

Red - Primary to HV
Blue - One side of the output tube plates
Brown - Other side of output tube plates
Secondary speaker taps don't really have a standard except for the ground lead being black. Other than that, I use an Ohm meter to figure which tap is which.

[Zombie_stomp]

So I wonder if the weber kit has correct colors. I'll have to learn to identify what each wire supplies to relate it to any schematic.

I think anyone viewing my photos can see the wire colors, but I may draw a layout of the way it is currently and at least through process of elimination, see what remaining stray wires go where.

Can I secure loose wires away from the chassis and carefully measure the output of the wires with nothing attached?

[Phil_S]

So I wonder if the weber kit has correct colors. I'll have to learn to identify what each wire supplies to relate it to any schematic.

There is no prevailing enforceable standard. Don't expect consistency. Weber publishes accurate diagrams showing color codes.

I think anyone viewing my photos can see the wire colors, but I may draw a layout of the way it is currently and at least through process of elimination, see what remaining stray wires go where.

Certainly can't hurt and it's a good practice.

Can I secure loose wires away from the chassis and carefully measure the output of the wires with nothing attached?

Yes. I like to use the type of terminal strip that uses screws to secure the wires. Example here: http://www.alliedelec.com/search/produc ... U=70212380 As a temporary measure, you can stick one to the chassis with double sided tape and then remove it when you are done. You can probably find one at rat shack.

[Zombie_stomp]

Mark, you provided schematic and layout for 5c3p octal preamp, Phil, you showed me the 5e3p with a 12ax7 preamp. I'm hearing all kinds of wonderful things about using the octal tube preamp, as well as a lot of problems with microphony.

The cheap route would be to make it with the 12ax7 because I already have one and the sockets. But the octal tube sounds so tempting!

[Phil_S]

This is your first build. Go for the 12AX7. If you get an octal tube that's troublesome, it isn't worth it.

[Zombie_stomp]

Cool, I finally tracked down their bill of materials for the 5e3p. Soon I'll be ready to order.

WAIT, SHIT! they don't have that BOM available on the DIY kits page. Is there some voodoo I gotta work to get that BOM without analyzing the two (5e and 5c) schematics side by side?

EDIT: I've emailed weber for the BOM for the 5e3p, they have provided kne for me for a different one before so it should work out. Meanwhile, I've printed out the layout and have it next to the amp so I can line up everything else while I order and wait for parts.

[Zombie_stomp]

I took stock of the values of components on the layout on the 5e3p amp design. I then found what I believe to be the right part numbers based on bills of materials for other amp designs near in model number found in the Weber 'a-la-carte' section of their website. The only thing I'm not positive about is all the voltages for the capacitors, otherwise I'd go ahead and order now. I may want to wait for an e-mail from weber, if they're willing and able to provide a bill of materials for the 5e3-p amp. If not, I'll have to assume the voltages are about right from the other similar amps and build, unless someone here can verify. See photo.

[M Fowler]

Here is the BOM

[eniam rognab]

looks like fun! enjoy it!