[AMRadio] AM

rbethman rbethman at comcast.net
Thu Jan 15 07:14:10 EST 2015

Rob and Geoff have hit it squarely on the head!

You can add insult to injury by reading 42CFR Part 97.

The 1500W PEP is to be measured "At the input to the antenna.". [Is this 
the shack end of the feed-line, or is it at the actual junction of 
feed-line and radiating element?]

Now how this is to be achieved, and using *what* to measure it with is 
left hanging in the air!

The amateur community has been brainwashed into the almighty Bird 
Wattmeter is "the standard".

Unless it has been sent in for calibration, AND the elements that go 
with it, you have no idea whatsoever what you are really reading.

The FCC doesn't specify WHAT you are to measure it with.

So simply do as Rob has stated, and get on with it.

Regards, Bob - N0DGN

On 1/15/2015 6:13 AM, Rob Atkinson wrote:
> "375 watts" and "PEP" are ridiculous concepts developed for the modern
> era of slopbucket/CW linear amps, cheap hammy watt meters and should
> not be a part of RF power conversations in the realistic AM world in
> my opinion.
> No one can precisely measure PEP or "375 watts."  Rarely does anyone
> operate into a 50 J0 load.  Let's quit kidding ourselves.  Just run
> whatever carrier you can get out of your rig, modulate it to near 100%
> negative and move on.
> The exception is for anyone who has never in his life driven over the
> speed limit on US highways.  If you are one of those types you may go
> ahead and obsess over the 375 watt nonsense.
> 73
> Rob
> K5UJ

Bob - N0DGN

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