minimize undesired positive feedback through careful design.
this design may require a phase shift in the feedback path.
the component introduced to effect this phase shift will
resonate with the rest of the circuit at come frequency and
if this resonance results in a new positive feedback it is
easily dealt with by way of heavy parallel damping.
none of this REQUIRES the introduction of a series resistance
with it's associated reduction in efficiency...
like I said below. if the designer cares to trade efficiency
for design effort and time, the NiCr device is an excellent
approach. likewise, if one is stuck with an existing bad
design the NiCr device can be a very attractive 'fix' when
compared to the alternatives, making the tradeoff acceptable.
there's more than one way to skin a cat and the best way
often depends on the cat and what one wants to do with it,
and/or it's skin, once they've parted company.
-bob
ah7i
2 wrote:
>
>>Exactamundo.
>>This is why the darn Low Q beast is undesireable.
>>
>>The only problems that a low Q supressor solves that aren't solved
>>by the Hi-Q suppressor are:
>>
>>1)It eliminates the requirement for selecting an L that provides
>>the correct phase shift to eliminate the problematic positive
>>feedback in a particular amplifier design thereby reducing the
>>mental exercise required of the designer who may lack the ability
>>to perform the exercise in the first place.
>>
>>2)It eliminates FUD over the possible failure of the parallel R in
>>the High Q suppressor resulting in a new positive feedback situation
>>at a different frequency, caused by the introduction of that L in
>>the first place.
>>
>>For these reasons, it's a good product.
>>
>>However, with careful design derived from an understanding of the
>>physics involved in an amplifier, it's an unnecessary tradeoff
>>with regard to overall efficiency.
>>
>>So, all you guys can quit arguing about the damn thing.
>>Yes, it works.
>>Yes, it solves a problem.
>>Yes, the problem can be solved in better ways.
>
>
> ** please describe one of these ways. Thanks.
>
>
>>....
>
>
> - R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> www.vcnet.com/measures.
> end
>
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