The nay-sayers suggest that this http://www.qsl.net/ve5ri/cyclops.htm
successful 160-10M contest-tested Eimac 4CX1500B power tetrode amp
is sub-standard in design and may suffer as to spectral purity.
Have you measured one built like this with the same tube and
found any of those negative claims to be true?
I am curious if the negative assertions are true or are mere
extrapolation from other tubes in vaguely similar designs.
I am also curious if the amp adds impurities or if most of
any garbage may be spectral impurities amplified from the
driver used in the tests performed by some.
Other "it can't work", "it only happens 300+ times by accident",
"that tube won't work that way", etc. things have been said of
572b amp conversions to 6.
The concept of "It's never been done that way before" or
"It didn't work when *I* tried it" troubles me. This is an
experimenter's hobby not a technological "sameville", we
need to feel free to imagine what may be possible and to
be open to the possibility that none of us know it all!
Edison succeeded through many more failures than successes,
and he discovered/invented technologies that most others
said could never be done or would never work the way he
was approaching them - he was frequently proved right and
them wrong.
Many were convinced that a nuclear reaction would set off
a chain-reaction that would destroy the entirety of creation.
They were wrong.
The lessons of history are replete with the failure of
limited vision and presumptions that what is unfamiliar
cannot work.
Of course, doing the same thing over and over expecting
a different outcome is an element of a diagnosis of insanity
but when folks build the same amplifier the same way over and
over and it is stable and effective the claims of others that
it cannot work do sound technologically absurd.
The scientific method says that one has successfully discerned
a scientific *fact* if one can describe and repeat an event
or interaction. A 6M amplifier using a pair of 572b's has
been described and repeated successfully. In the scientific
world no-one would challenge that as fact.
Many components in rf circuits were designed for a specific
purpose and the designers wrote specs in that narrow context.
The designers *never* specified that their device could *never*
be used in any other context and work. They were silent on that
as it was not their task-description.
That others have discovered new and different ways to utilize
devices outside of their initial design parameters is not to
be criticized but praised - it is and has always been one of
the most valued elements of our experimenter-Ham hobby!
A transistor designed to be an amplifier may also be used as
a diode, a 120v - 12v power transformer as an audio transformer,
a piece of metal fence post used as part of an antenna, and on
and on.
Artificially limiting creativity to small predictable boxes
is boring and destructive to advancement.
WDYT?
> That design has nothing to do with neutralization, there is none.
> It´s just passive grid, I did that quite often with tetrodes and it always
> worked very well for me.
>
> 73
> Peter
>
>
> To this amateur Amateur the design concept here looks really elegant:
> http://www.qsl.net/ve5ri/cyclops.htm
>
> What is the perspective of the assembled amplifier-gurus?
>
> It sounds as though he has engineered a more-simple solution. Have others
> done this before and since and found it valid or wanting, please?
--
Thanks! & 73, doc, KD4E
Personal: http://bibleseven.com/kd4e.html
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