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Originally Posted by dcfis
 I can solder pretty good but Id have to have "put this there directions"
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The problem about DIY tube gear isn't the instructions either. Lotsa kits have excellent instructions, Bottlehead/VALVE/Electronic Tonalities kits for instance, in Europe the fine Velleman kits. There are only a few kinds of components and their ratings are usually printed on them to make it easier.
The problem about DIY tube gear is that you need to learn at least enough about electricity to be able test and adjust the built amp safely in the presence of life-threatening voltages. That can take a little study because you need to know enough about how the amp works to be able to reduce the number of times you put your hands into it to a minimum, and to do whatever needs to be done accurately and safely the first time; it is stupid to mess around without a plan in box with hundreds of volts inside it. You also you need someone experienced to show you and to stand by the first few times you do it; elderly radio hams helped me when I started out. All of these requirements can slow down your first tube kit quite a bit.
Anecdote warning: About ten years ago I published a whole series of related 300B amp circuits people could build with only one big transformer hit in the wallet, or a progressive expenditure by starting cheap and adding complications. This got a lot of publicity and far more people than I expected actually built the amps. Of those who wrote to me, more than half were buying a soldering iron and a multimeter for the first time to work on a 500V amp as their first project. Nuts! These guys weren't technicians of any kind (techies tend to choose my PP amps to build because PP is more efficient), and the one who was an engineer built sewerage works. I was horrified at the risk they ran. A couple of years later I decided not to publish the designs of my kilovolt T99 Millennium's End 75W SE amp for fear that someone would kill himself trying to build it without a proper understanding of what he was dealing with. A fellow at the university said I shouldn't be so wimpish and showed me a device they have which they measure with a probe on the end of a two-meter glassfiber rod because it is such high tension electricity, it will jump a gap of a couple of *feet*. Of course, that's pretty extreme, but you don't actually need to touch much lower voltages; they too will jump a gap to your skin. Someone also needs to tell you simple things, like taking off your jewellery before you put your hand (one hand, the other should be in your pocket or behind your back) anywhere near electricity, and how to discharge capacitors. A charged up 220uF cap at a few hundred volts just brushed with a wedding ring contains enough energy to cook your finger; it might have to be amputated; at the very least you'll have a nasty burn.
I'm not trying to put you off DIY tube amps but it is in your own interest to learn how to work safely with high voltages, and to take great care.
Here's a good question to ask yourself: If you aren't paranoid, why are you working with high voltage tube amps?
BTW, a kit is one thing, a scratchbuild quite another. Unless you really know what you're doing, or the kit designer provides a complete parts list with catalogue numbers from a single supplier, don't even think about it. Small example of how you can go wrong: most resistors in mailorder catalogues are not rated for valve voltages; you need to check the ratings with the manufacturers if the catalogue doesn't give them. If you're scratchbuilding the cost of carriage from several suppliers, and the cost of even halfway decent casework, can make the complete project cost two or three times as much as a premium commercial product.
Andre Jute
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