>
>> My engineering background and professional experience are in digital
>> design and software engineering, not RF design. Disentangling their
>> technical arguments would take more effort than I care to spend.
>
>The arguments aren't all that tangled.
>
>My conclusions are based on my experience and
>measurements...and knowing what fails in the field as a percentage
>of what goes out based on feedback over the past twenty years
>
>My conclusions are all rooted in provable documented science, and
>not based on any personal issue.
>
>> my amplifiers (AL1200, SB220, SB201) has ever flash-banged, so I'd rather
>> spend what free time I have chasing DX or writing station automation
>> software. But a competent RF engineer should have little difficulty,
>> particularly with the tools available today:
>
>That's true.
>
>> 1. select an appropriate circuit modeling program
>
>Why model when you can measure?
>
>> 2. construct a model of the tube in question, parametizing manufacturing
>> variances
>
>Why model when you can measure?
>
>> 3. construct a model of an amplifier circuit in question, parametizing
>> component tolerances
>
>Why model when you can measure?
>
>> 4. discover combinations of parameters, if any, under which VHF
>> oscillation occurs
>
>That can easily be done, through measurements and an
>understanding of basic RF systems.
>
>> 5. construct models of alternative VHF oscillation-suppressing circuits,
>> and evaluate their effectiveness and side-effects
>
>N7WS ran calculations and reached an independent conclusion.
>After he reached the conclusion and published an e-mail asking
>him to change his position by one of the parties in the debate, he
>was personally attacked.
>
>Anyone doubting this can ask N7WS directly.
>
>> does not oscillate. Evaluating the effectiveness of suppressor circuits is
>> a similarly-objective excersize.
>
>It isn't that complicated. Models are useful for a system that is too
>complicated to be measured and analyzed as a real system.
>Models are shortcuts.
>
>> I suspect that neither combatant is truly interested in resolving the
>> underlying technical issue; doing so would terminate their righteous
>> justification for continuously elbowing and needling each other. It won't
>> stop until Rich publicly admits that he profits by selling unnecessary, if
>> not harmful, add-ons to ignorant amplifier owners,
>
>Profits come from more than cash. Some profits are in the form of
>notoriety. The nichrome isn't harmful, it is the theories that ruin the
>ability of people to understand the complex workings of a PA that
>are harmful.
>
>There are harmful mods he suggests, such as removing grid
>protection circuits.
The grid protection circuits I am talking about are those that provide no
protection because the transistor that interrupts has too low a current
rating and it shorts during a glitch -- thereby affording no protection.
> He suggests using
? (frangible)
>resistors for fuses to protect
>grids. He also suggests increasing the size of equalizing resistors
>in amplifiers, when those resistors were selected to have the
>maximum possible resistance to do an effective job. Those
>changes are harmful.
>
We have sold over 6000 of the 100k-ohm, 3w Matsushita resistors. There
have been no reports of problems. The main advantage of these resistors
is that they do not overheat filter capacitors.
>> or until Tom admits
>> that he intentionally designed self-destructive amplifier circuits on
>> behalf of his quality-insensitive employers and hid this malfeasance by
>> using the influence of those employers to suppress Rich's whistle-blowing
>> ARRL handbook article. We'll be reverse-engineering humans from their
>> genomes before either of those things happens.
>
>I suppose that could be correct. This is how it would have to have
>worked:
>
>I would have had to have been ordered to design amplifiers to fail so
>the manufacturer's could spend extra money on warranty service.
>Dick Erhorn would have to have decided to design amplifiers that
>ate 8877's in the 80's, just like I was order to do, just so the
>companies would get returned products and service headaches,
>and lose sales.
>
zzz
>Eimac had to be part of this conspiracy, since they covered up the
>manufacturer's intentional flaws by issuing hundreds of thousands
>of dollars of credits for defective tubes that really weren't defective.
>
A cure for insomnia.
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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