Amps
[Top] [All Lists]

Re: [Amps] Measuring RF Power

To: David Kirkby <david.kirkby@onetel.net>
Subject: Re: [Amps] Measuring RF Power
From: R.Measures <r@somis.org>
Date: Sun, 27 Mar 2005 08:13:11 -0800
List-post: <mailto:amps@contesting.com>
On Mar 27, 2005, at 7:32 AM, David Kirkby wrote:

> R. Measures wrote:
>
>>> 2) People who were wrong, and don't wish to admit it.
>>
>>
>> chortle
>
> It's just childishness to hang on to an argument if you know you are 
> wrong.

I have observed that the tightest-gripped hanger-on-ers are not children
>
> There is nothing wrong with not knowing that RMS power and mean power 
> were the same. I have freely admitted that I'd never considered the 
> issue before.
>
> Furthermore, had someone asked me, then I too would have no doubt 
> thought that the I_rms*V_rms=P_rms. It seems most natural to me. 
> Others have said it is a widely held misconception.
>
> I know an ex-colleague of mine, went to a local HiFi shop to buy some 
> HiFi. The guy in the HiFi shop was giving it all the sales talk on the 
> power of this amplifier, thinking she was a dumb blonde. She was 
> blonde, but not exactly dumb as she had a PhD in physics.

PhD diplomas are available on the Internet these days.  One of the most 
ohm's law-ignorant Hams I ever met told me that he had a PhD in 
electronics engineering.
>
> So she questioned him if the power was RMS, or some musical thing with 
> no basis. At this point he realised she was not so stupid. But it 
> seems she was wrong to question if the power was RMS, but mean would 
> have been the technically correct term. (I'm also aware that for 
> music, there is some logic in having an amplifier capable of producing 
> high peak powers for short periods with little distortion, but not be 
> capable of producting such powers on a continuous basis).

Good point.  For shaker-tables, RMS power is it, but for music, PEP-IMD 
  is more relevant.
>
> But I can't help but feel it was childish


> to send a one worded reply of "bananas" when I asked you to 
> substantiate what you were saying, or find a fault in my analysis.  It 
> would have been much better to either
>
> a) Substantiate your argument.
> b) Find a flaw in mine.
> c) Admit you did not follow my maths - I would have had more respect 
> for you doing that, than you gained by silly one word responses.

Some people grow up and some people don't.  The girl who used to do 
mail orders for me said that I have the mind of a 12-yr old.  If 
someone challenged me to conclusively prove that R = E / I, My response 
would be either:
1.  bananas
or
2. coconuts
or
3. _____
>
>>> ...

cheerz, David

Richard L. Measures, AG6K, 805.386.3734.  www.somis.org

_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>