Need a tech lesson-How to read the tube datasheet-can you give your contribute ?

[kagliostro]

Please I need a technical lesson

I would like to learn how to understand more the data on tube datasheet

have you a link for that or can you give news as to correctly afford the read of a datasheet ?

Many Thanks

Kagliostro

[jjasilli]

A couple of members, including Butterylisciuos, gave some great tutorials (to me among others) on load lines.      I can't find the thread(s).       Maybe someone will remember. 

Meanwhile, what specifically do you want to address?     Usually the first hurdles are the max ratings, then tables of typical operation.  Then there's the dreaded tube curves.   

 

[Fresh_Start]

What are you trying to figure out?

Here's the best tube data search I've found:
http://www.mif.pg.gda.pl/homepages/frank/vs.html

Enter 6L6, then select the G.E. 1963 sheet for a 6L6GC.  

The "Maximum Ratings" are always useful.  On some older data sheets, they refer to "Design Center Maximum" IIRC.  It's not quite the same thing, and I think the "Design Center" figures typically are lower.

On page 2, it shows typical operating conditions.  A treasure trove of good info!  Unfortunately, the supply voltages tend to be lower than what you find in modern amps.

Then you hit the graphs.  I still have a hard time understanding these because they typically show 3 variables at the same time.  Merlin a.k.a. "Valve Wizard" has great info on using the graphs HERE for triodes.  His pentode section isn't about power tubes, but helpful:
http://www.freewebs.com/valvewizard/pentode.html

I used to have a link to an essay called "Understanding Load Lines" but can't find it.  Anybody else familiar with it?

Hope this helps,

Chip

[triode]

PRR has a way of presenting things to people that make it easy to understand. I was reading a
thread of his a while back and thought some other people would find it useful at the time...
so I asked PRR if I could recreate this thread in a pdf this a few years back, he said ok, so here it is again...

LoadLinesbyPRR...


http://theairtightgarage.com/gallery/loadlinesbyprr.pdf

[Fresh_Start]

PRR has a way of presenting things to people that make it easy to understand. I was reading a
thread of his a while back and thought some other people would find it useful at the time...
so I asked PRR if I could recreate this thread in a pdf this a few years back, he said ok, so here it is again...

LoadLinesbyPRR...


http://theairtightgarage.com/gallery/loadlinesbyprr.pdf

Many thanks to Triode and PRR!

[kagliostro]

Many thanks to all for the given advices and infos

tables of typical operation.  Then there's the dreaded tube curves

those are two things that I would like to understand better

Many thanks also for the given links with first class infos

Kagliostro
 

[simonallaway]

The opening chapters of Merlin's book on pre-amp design is very good on how the curves relate to the circuit. As a newbie I got a lot out of it.

[Fresh_Start]

The opening chapters of Merlin's book on pre-amp design is very good on how the curves relate to the circuit. As a newbie I got a lot out of it.

Merlin is nice enough to provide the entire first chapter of his preamp book here:
http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf

That's what I intended to link to in my earlier post, and it is good albeit without the stained napkin in PRR's discussion

Chip