>
>Steve says:
>
>>What is a reasonable value for the source impedance of the rectifier.
>
>I looked this up and posted it a while back. The rectifier resistance is of
>the order of 8 to 15 ohms (it varies with current) so the total source
>resistnace isn't going to exceed about 350 to 400 ohms. The original G2DAF
>used a total of .007 microfarads screen bypassing/ reservoir capacity, so
>the the tc is a bit under 3 microseconds. So if it takes 5 tc's to charge, I
>make it that 99.33% of the voltage will be reached in under 15 microseconds.
>So the bandwidth of the system (from rise time multiplied by bandwidth =
>.35) is about 23kHz. As this is about 10 times the signal bandwidth, prima
>facie, there shouldn't be a problem.
>
In the observed feculence area - DAFs seemingly perform roughly 10x
better on two-tone tests than they do in on the air voice tests. During
two-tone tests, screen potential is constant. During voice operation,
screen potential is not constant. Why are we arguing about whether or not
one can keep a screen bypass C sufficiently charged at all times during
voice operation? I say do it or rue it.
>And I still don't like the G2DAF! Don't forget that at the time, there was a
>lot of argument in the RSGB Technical Committee circles about it; G6JP (who
>worked in the design, manufacture and applications of valves for the M-O
>Valve company all his working life and served on some of the International
>Electrotechnical Committees as a UK delegate) openly criticised the design
>in the letters page of the RSGB Bulletin, as it then was, on grounds of
>linearity.
good show
>
>Technicalities apart, there was a definite attitude in some parts of RSGB at
>that time that anything G2DAF did or said was right, and those disagreeing
>were cast beyond the pale into the outer darkness with much wailing and
>gnashing of teeth......
Indeed, indeed. Based on what I have heard so far, my guess is that
Thornley was a charismatic person who was skilled at fulfilling unmet
needs of the ''inner-child'' (John Bradshaw). This is basically what
Bagwan Rajneesh did for members of his cult. . In my opinion,
fulfilling unfulfilled needs is perhaps the greatest of human weaknesses.
However, this area is undoubtedly a two-way street. The Bagwan played
the role of the missing dad. The followers played the role of
unfulfilled children.
> ....a number of professional engineers working in SSB
>design were 'sidelined' out of the way of RSGB position for disagreeing,
Disagreeing with a charismatic person is a risky pursuit. Those who
question the beloved guru / father-figure must contend with attacks by
faithful lap-dogs/true believers. . . So far, I have received two death
threats from devout followers of a charismatic person.
> as
>I heard it. One of the guys who told me a lot of this has just gone SK,
>unfortunately.
>
The only thing that a man can take with him into the land of silent-keys
is respect.
>
cheers, Peter
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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