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[AMPS] IMD Question

To: <amps@contesting.com>
Subject: [AMPS] IMD Question
From: watson@epiloglaser.com (George K. Watson)
Date: Mon, 14 Feb 2000 13:43:49 -0700

>>The only way to measure fundamental power without harmonic contribution is
>>with a tuned receiver or spectrum analyzer.

And the entire system has to be calibrated as just slapping a low pass on
the line and measuring power will introduce losses at the fundamental.

>>If this is being observed with an untuned power meter, it is likely
because
>>MOSFETs and FETs readily generate copius amounts of odd-order harmonic
>>energy, most notably 3rd and 5th harmonics.

Isn't this a bit topology dependant? (Which harmonics are generated)

>>Bipolar RF power transistors are built with and without emitter resistance
>>which introduces negative feedback.

Aren't there MOSFETS with 'built in' source resistors? I had heard this
somewhere.

George
K0IW


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