Re: 3 dB bandwidth




Keith Williams wrote:

>> Given the repeated basic errors that the poster in question has made,
>> I was not sure whether he meant voltage when he wrote "potential"
>> Thus my usage of "appears to be." One can't be too careful when dealing
>> with the ineducable; sometimes they appear to make sense when actually
>> they are simply lacking the vocabulary to express their ignorance.
>
>What does "impedance matching" or "maximum power transfer" mean to you?
>Hint: It's a R/R+R voltage divider.

I would agree if the statement was made by a "normal" person, but I
have found that the ineducable can, by random chance, stumble on to
the correct terminology without having any real understanding. Thus
my usage of "appears to be."

>> >Do you have a problem calculating 20log(.5)?
>>
>> Nope. Do *you* have a problem calculating 10log(.5)?
>
>Well, a *voltage* divider divides, um, voltage. Thus 20log(.5) or 6dB.

Decibels are units of power, not voltage.

>> "bel (B): A unit of measure of ratios of power levels, i.e., relative
>> power levels. Note 1: The number of bels for a given ratio of power
>> levels is calculated by taking the logarithm, to the base 10, of
>> the ratio. Mathematically, the number of bels is calculated as
>> B = log10(P 1/P 2) where P 1 and P 2 are power levels. Note 2: The
>> dB, equal to 0.1 B, is a more commonly used unit."
>> Source: http://www.atis.org/tg2k/_bel.html
>
>Wow, you know how to use Google. Now try learning something about
>electronics.

The children who played with Mattel's best selling new toy for the
year 2000 and the pilots who fly airlanes tested with my AV-8B Harrier
actuator test system seem to be satisfied with my abilities.

I deleted the rest of whatever you had to say unread. My time is too
valuable to waste on someone who thinks that personal attacks are a
substitute for a civil discussion of the topic at hand.

*plonk*

.

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