> Help me here. Isn't this the purpose of the suppressor? That is , it's
> function in design is not only to limit parasitic currents to a
> "negligible level," but more importantly "suppress" the oscillation from
> occuring "in the first place?"
The goal is to prevent oscillation. That's done generally done by
inserting a series resistance that is reasonably large compared to
the anode path impedance.
The shorter the anode lead, and less reactive, the less resistance
you need add. Other things come into play also, but it isn't
extremely complicated.
> Perhaps, unless Rich uses the material "in fair use," as provided for in
> the U.S. copyright law. Additionally, violations to copyright law are not
> limited to "for profit" references. Adding web links for general
> distribution (e.g., Wes's link to this mail list) without the express
> consent of the copyright holder can also lead to copyright infringement.
I think the main complaint by Wes was a gentleman's agreement
to NOT corrupt or distort the data was broken.
You should ask Wes about that.
> I too am perplexed by the ongoing suppressor controversey and it's
> function seems to be nearly as mystical as that accorded by the dreaded
> balun.
Baluns are easily understood, except for those who want it to be a
simple one word answer.
> nearly every commercially-manufactured amateur amplifiers when most of the
> same manufacturers would have you believe that 1) their amplifiers are
> ultimately stable, and 2) suppressors are not required in
> "well-engineered" designs. If conditions 1 & 2 are met, isn't it
> ridiculous to include the suppressors in their designs? Or, is the
> inclusion of the suppressor in their amplifiers that little bit of
> insurance against "the unknown?"
In some cases suppressors are needed, in some they are not.
Sometimes they are included just because people think they
should be there.
> Seems like Rich has worked toward an alternative method suppressing
> parasitics that is no more costly or dangerous to the performance of a
> H.F. amplifier's design than that provided for by the standard use of the
> classic coiled wire on a carbon composition resistor.
There is little harmful in using his suppressors. The real harm is in
the wave of sideways thinking that has been produced by bad
theories and junk science surround the causes of failures.
The only harmful advice I'm aware of is his suggestion that grid
protection circuits are not necessary in metal oxide cathode tube
amplifiers.
While the nichrome doesn't fix much if anything, it only hurts ten
and 15 meter efficiency bit. So it really isn't harmful.
73, Tom W8JI
w8ji@contesting.com
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