• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Who makes nice pc board for tubes ?

I have used Expresspcb for several tube projects,they not quite to the specs you listed, but They have performed nicely in all my projects.
 

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I have used Expresspcb for several tube projects,they not quite to the specs you listed, but They have performed nicely in all my projects.

I agree with Denny and use ExpressPCB a lot.

Are you looking to make your own or are you just looking for a tube amp kit?

If the latter is true, can you provide us with what you are trying to build?
 
I agree with Denny and use ExpressPCB a lot.

Are you looking to make your own or are you just looking for a tube amp kit?

If the latter is true, can you provide us with what you are trying to build?

The current board you see is for an SCA-35, that's undergoing restoration. Most of what I do is restorations,with a few being my own designs.

ExpressPCB can be a little pricey on certain designs but you can maximize cost if you consolidate circuits. Take PC-10 found in the SCA-35 Dynaco used two separate boards for the amp section,consolidating both channels on one board,kills two birds with one stone.
 
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For some reason, from reading the forum run by the two guys that own Tubes4HiFi.com, one of the is working on putting together a kit for building a new SCA-35. I'm pretty sure if they do its nots going to be a direct replacement. They usually modify the design to accept modern improved components and do what every they think is an improvement to the circuitry.
 
I have used Expresspcb for several tube projects,they not quite to the specs you listed, but They have performed nicely in all my projects.

I bought the program Copper Connection by Robot Room. The $49 Studio version will read the latest version files created by ExpressPCB and generate Gerber and Excellon files. Then you can use a source such as ITEAD Studio as mentioned earlier.

I have no affiliation with Robot Room other than I own the product.

Scott
 
For some reason, from reading the forum run by the two guys that own Tubes4HiFi.com, one of the is working on putting together a kit for building a new SCA-35. I'm pretty sure if they do its nots going to be a direct replacement. They usually modify the design to accept modern improved components and do what every they think is an improvement to the circuitry.

My thinking is that they will do away with the tone controls, because of the sourcing of the parts,the dual 2M dual pot used for the bass control is not found in current production as well as the 750k dual balance pot,and I'm sure they will use the curcuit found in the infamous ST-35 for the power amp section.,and finally the phono curcuit used by Dynaco is not up to current RIAA specs,so the phono section would most likely be modified. I love the idea of an SCA-35 kit none the less,those mods would make for a great little integrated amp.
 
I'd check with the owners of the web site. I has virtually all the boards to reproduce a PAS-3 preamp that has tone controls and a phono circuit. He does sell phono preamps and kits as well. I have an SP-12 preamp I had him build....so my phono preamp will be separate if I ever get a turntable. I was thinking I will but I've got maybe 60% of my LPs on CD and now my taste in music has changed so I no longer think its absolutely necessary.
 
I'd check with the owners of the web site. I has virtually all the boards to reproduce a PAS-3 preamp that has tone controls and a phono circuit. He does sell phono preamps and kits as well. I have an SP-12 preamp I had him build....so my phono preamp will be separate if I ever get a turntable. I was thinking I will but I've got maybe 60% of my LPs on CD and now my taste in music has changed so I no longer think its absolutely necessary.
I have one of the Tubes4hifi PAS3 boards with the tone controls that is still in process. It drops right in the PAS3 chassis. The only thing I do not like about the boards is this one doesn't have silk screen and mask. It's not a huge deal but for the cost I think they should as it's only a bit more for the boards to have it done. Can't say how it sounds yet.

Not sure if I got the comment right but someone was asking why the thicker PCB material. If you are doing preamp small tube small board it's fine, if you have a larger board and octal or larger power tubes without question spend the extra couple of bucks on the thicker material. I have done both and will never use the thin stuff unless for a prototype.

Advanced PCB has some prototype pricing, but don't expect anything to be inexpensive, extra thick, masks, silkscreen all adds up. Look for the specials, I have done the 33 bucks each (min 4) for standard thick board.

Printed Circuit Board Full Spec 2-Layer PCB Design Specials.

Sandy
 
Don't know why others might opt for 2oz copper, I generally will spec it for tube project.

When running higher current filament and other lines it allows you to have a thinner width trace as well as keep the voltage drop down. For things like the Ground bus it's also lower the overall resistance which I'm told is a good thing to keep things quiet. You can do the same if you make the trace wider however that sometimes is not practical for routing a board, for example on the Quad KT88/KT120 you need to account for 8 amps of current to the set of tubes. The traces width for that gets wide and difficult to route on a tight board.

Others may have their opinion, but again, on a small quantity of boards the up charge is a couple of bucks as is the high temp material if desired unless you get the generic prototype which is usually the least expensive.

I have not run into any board warping on a smaller tube amp (6V6PP) board with 0.063" material and it's been on for 6-8 a day for 4 months now. One thing that I do place a lot of is holes for supporting the board. This is important to keep from having a mechanical problem with tube removal/inserts. I HATE the feeling of PCB's that are not fastened securly when you put a tube in. If it does not feel like a chassis mounted socket when you put a tube in you don't have enough support for your board! The thicker PCB (0.095" or close) helps a lot with the board flex problem as well as a good amount of mounts.

Sandy