• 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.

On Line Tube Learning for newbies....

Is there such a thing as online reference for designing a high voltage power supply? 1kV and up?

What I'm asking is is there an easy to understand reference for all of the quirks associated with high voltage supplies?

I know that most theory for low voltage supplies can be scaled up but only to a certian excent and most of them do themselves an injustice by not permitting the reader to confidently design an even higher voltage supply.

Or is it all based upon prior-experience and hand to hand knowledge?

For example, why is it necessary to have a greater amount of filtering capacitance for higher voltages, I'm assuming that it is because the ripple has a greater effect, but I'm not sure, thats a problem.

I do know that SS rectifiers induce noise more so than vacuum tube rectifiers because the SS diodes cannot deal with the flowback of current as easily as tube based rectifiers.

Tube based rectifiers are /nearly/ mandatory in a high voltage power supply as they have far greater peak inverse voltage ratings and with Mercury/Xenon tubes have extremely large peak and constant current ratings.

Rubber insulation on transformer secondary and anode caps aswell as in the case of a resistor network and last but not least capacitors, also be sure to keep HV cables away from the chassis as arc-over can occur.

I'm considering a pair of the GXU1 for a 1kV 300mA supply but I can't find a suitable choke, I'll most likely have to make a custom choke, anyone you know of which manufacture chokes with suitable choke-input ratings of at least 1.2kV and at least 500-600mA?

What I do know is that current draw of resistors needs to be heavily monitored as you don't want to dissipate 300w of power, so most resistance in a filtering scheme is impossible to implement in high voltage supplies without heavy heatsinking.

Components have limitations on current draw and maximum working voltages, all working voltages for chokes and capacitors must be greater than peaks, but if the peak is only 20% greater than the limitation for only one second or less and it occurrs only once (upon startup) then it should be okay.

In Choke input supplies, chokes must at least have 50% or greater than capacitor-input limits so they can handle the inrush current of the further filtering capacitors, in a cap input supply the first capacitor hogs all amperage and that is why chokes are of a lower value.

There are a few other things, most important, but I cannot for the life of me remember what they are.
 
GRollins said:
There was a post earlier for the glossary, but not for the main website:
www.tubecad.com
Grey


Uhm I won't bash John Broskie's rather excellent Journal's but I will on his Glossary, it sucks, are there any other glossarys which contain more than 30-40 descriptions online that cater for the tube side of the web?

Ie, There simply isn't enough, Tubes are a vastly larger world than from A to Z than in 30 words/abbreviations.

I would imagine many newcomers reading this thread are becoming quite confused when the only immediate referential glossary material to them is online/electronic and 1/4's done.

Remember we're trying to teach newcomers not previous field workers whom know the lingo, I bet you that 1/2 of the newcomers whom frequent here for learning have no way to refer to a book for a good referential glossary any time they want and is absent from quite a bit of beginners learning material, but if it is it's hard to source, this affects my understanding of the field quite a bit because I find myself re-learning the same stuff a day or a week later, whenever I have enough balls to give it another go, If I had a dictionary I guarantee you I could learn twice as fast than I am now.

The big Engineer's reference book for tubes and other closely associated fields are just not being redistributed and the copy my uncle lends me is deteriorating fast.

Please diyaudio.com/tubes, come out with a pocketbook that people can print and take with them that has every damn description out there, wether the user is learning how to properly do the numbers on a filtering stage or wether they're calculating interelectrode capacitance for elements in some wild and wacky unexplored tube, they/we/I need a dictionary.
 
Great scott!

My fingers hurt from adding all your links to my Favorets:D
Look´s like me and posibly 9am53 are the only tube noobs on this post so here goes: For me you shouldn´t have. But seriosly thanx a lot! this is the most helpfull forum I´ve seen and by helpfull Im talking about the members and youre willingness to help and inform the newcomers:)
 
Thanks so much to everyone for posting this information. I've been reading for days, and now I feel like I only am confused by 98% of what I see! Today I looked at a schematic on this site and understood that it was single-end, what the two tubes were for, and why the output transfomer (or OPT, as I learned after hours of confusion) was where it was. I still feel completely overwhelmed but I'll plug on because I WANT MY TUBE AMP!! :)
 
It is very valuable information on that site:
http://www.radau5.ch/basics.html

The english articles are using the US theory that is based on the conductance and the german articles are based on the perveance. Those german books are very interessant because the perveance is much more constant as the conductance when a tube is doing some dynamic work, even if at the end, the final result of a calculation must be the same.

German is not my cup of tee, but it is always the math...

Some books are very easy to read, other are very tecnical.