Measuring RF power/signal strength accurately is a non-trivial undertaking. I
strongly recommend the Keysight (nee Agilent nee Hewlett-Packard) tutorial:
http://rfmw.em.keysight.com/videos/PMPS_Introduction/index.htm
Or this older, more detailed treatment:
http://my.ece.ucsb.edu/York/Yorklab/Useful%20Stuff/Tutorials/RFPower_Meas%20AN64-1B.pdf
Both cover the complexity caused by different modulation types, bandwidths,
onset rise-time and numerous other factors. One fact that becomes clear is that
hobbyist meters are largely toys and, if you're going to use a 'toy', at least
get a good one. Larry Phipps N8LP of Telepost has designed the LP100A to be a
'baby Agilent' and periodically sends his reference gear out for calibration.
The best way to stay legal is to buy the best you can, with the best
traceability and adjust your power amplifier output to the lower uncertainly
limit of your meter. That's call you can do, and all you're required to do by
the regulations.
73,
Mike - N8MSA
----- Original Message -----
From: "KA4INM" <ka4inm@gmail.com>
To: "amps" <amps@contesting.com>
Sent: Sunday, May 3, 2015 3:59:11 PM
Subject: Re: [Amps] Time for New Power Meter
On 05/03/2015 03:23 PM, Steve Wright wrote:
> On 04/05/15 04:00, amps-request@contesting.com wrote:
>> Because of these limitations, I've come back to mostly using Drake W4 and
>> Bird Thruline meters with a home-brewed PEP amp board
> Not meaning to quote anyone in particular here, but what is this
> insecure fixation with watt meters?
> Do we want to not break the rules by ten watts? No, I do not care about
> ten watts over the limit, and neither do the authorities.
> Are we worried that we'll blow the amp up? No....
> What is it then?
I think it is a strange fixation that a few of us have,
trying to live within the law, I think I got mine from my pop.
He was that kind of guy.
--
Ron KA4INM - Youvan's corollary:
Every action results in unwanted side effects.
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