Well, a few more bones for the dogs:
I have to mention that I started to dig into my boxes of assorted components, hoping to use up stuff I else wouldn't. What's left was to order from local shops.
Transformers use, as I wrote earlier were cheap transformers used in totally different applications and I really wanted to use cheap but dedicated iron (read Edcor). After some consideration, a few mails to the journal's technical advisor and reading a follow-up article in wwhich the cheap Altronic's transformers were compared to Hamamatsu-something $1000 transformersI decied to go with the Altronic's:
M1115.
Mains transformer is a universal kind with several windings that are added to 116V and then run through a voltage doubler. I decided to order a special made toroid from Germany - that will be the project's most expensive part.
God, I should order some more of the Altronic X-formers. They could be useful in other projects where smaller tubes are used ...
I should add that I will not rush this project (but the PCB is already almost fully populated). The ieda was to add componets and parts littel by little but apart from some PCB connectors and a quadruple 470n/630V capacitors (I made a mistake when I order them and ordered TWO instead of FIVE
). I also miss a box to house the amp but I had two ideas. One wwas to use some golden sheet metal lying at my job, but that was thrown out before I said STOP. Another is to use a wooden box, either made to the measurments in the original article, or make something personal.
This is the original design:
Finally a word on PCBs. I prefer point-to-pint technique when wiring tube amps, but in this case I found it very handy to use the board to see how the project advances, what is needed for the next step (missing components) and most of all the board makes a good base. When everything's in place, I just hook up the mains transformer to test that everything is working.