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SV: [AMPS] G2DAF Circuit

To: <amps@contesting.com>
Subject: SV: [AMPS] G2DAF Circuit
From: 2@vc.net (measures)
Date: Sat, 28 Oct 2000 05:51:54 -0700
>
>Tom, 
>
>It was not intended as an insult, I thought there was room for some humour
>every now and then. Albert Einstein was not my friend and I thought that
>would shine through in the message. I appologise if you feel offended.
>
>I do get your point regarding the circuit but the point we are trying to
>make is that despite the fact that you and others try to tell us it doesn't
>work it does work. 

Everyone on AMPS knows it works.  The question is how much feculence.  

>WITH respectable IMD, the measurements that were carried
>out is proof of this. 

? DAF enthusiasts publish measurements that are pro-DAF.  

> I think we have done far more extensive testing of
>these amplifiers than many others have done with their homebrew stuff. Far
>more..
>
credible tests are performed by third parties, totally without warning.  

>Maybe we should not call our amps "DAF amps" as they are somewhat different
>as we use diodes and not tubes to generate screen voltage. Furthermore we
>use a different tube in the amplifier. We have said that the design might
>not be repeatable with every type of tube but with these ones (QBL5-3500)
>for sure it is. 
>In that regard this design is not different from other designs, there are
>some tubes that don't work well or aren't suited for GG for example. Then
>they should not be used in GG, of course. We're just trying to get across
>that under certain conditons the "DAF derivative" circuit can be used with
>a tube suited for it. That's it.
>
If your DAF amp measures minus  22db total IMD, YOU foolishly selected 
the wrong tube.  


>Mr DAF might very well have the wrong numbers in his article, I will not
>and have not contested you on that as you are much more capable to check
>them out than me. But that is another story.
>
>So, in the future I will not include any humorous or sarcastic remarks as
>we must be strictly scientific here. Good point.... :-|
>
Avoidance of humour is hardly appropriate for the DAFt circuit.  There is 
much fodder.  

later, Peter 
>
>
>
>
>
>At 11:05 2000-10-28 , you wrote:
>>> I would like to add the following statement from a good friend of mine:
>>> 
>>> "Great spirits have always encountered violent opposition from mediocre
>>> minds." -  Albert Einstein
>>> 
>>> Albert was right, look at the opposition we SM's get for rejuvenating an
>>> old design that has merits.
>>> 
>>> /Mr Peter, SM2CEW
>>
>>
>>Hi Peter,
>>
>>You and your friend miss the entire point of what I am saying.
>> 
>>You seem to feel the circuit is well designed, and has some merits 
>>that exceed it's potential for problems, but that just isn't true.
>>
>>Insulting others, because they point out a few technical facts, 
>>doesn't make your favorite circuit become a good design. The fact 
>>is, before you and your friend lifted my statements from context, is 
>>G2DAF himself has some technical gaffs in his article. Some of his 
>>numbers don't agree with themselves.
>>
>>You may take this as a personal insult against your mother if you 
>>like, but the fact remains that circuit does about everything you are 
>>not supposed to do with a linear PA. 

?  Amen to that, Mr. Rauch.  By simply regulating the screen, a more 
linear and more powerful amplifier could have been produced with the same 
tubes.   The DAF design basically came about from ignorance of how to 
regulate the screen potential.

>>If one or two work, that's fine 
>>with me. But it is not a good design. Because one or two of 
>>something can be made to work doesn't prove it is a repeatable 
>>design, or a good design.    
>>73, Tom W8JI

-  Rich..., 805.386.3734, www.vcnet.com/measures.  
end


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