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GENERATING OR ON THE RECEIVING END OF EMC PROBLEMS.  IN SUMMARY, THIS BOOK
VERY NICELY COVERS THE CONCEPTS AND UNDERLYING PRINCIPLES OF MANY TYPES OF
REAL LIFE MEASUREMENT SYSTEMS.  THE FOCUS IS CLEARLY ON PROFESSIONAL
APPLICATIONS, BUT THERE IS ENOUGH OVERLAP WITH CURRENT AMATEUR RADIO
TECHNOLOGY THAT MANY ADVANCED AMATEURS WILL ALSO FIND THE BOOK A GOOD
ADDITION TO THEIR TECHNICAL LIBRARIES.  THE MODERN MOBILE  RETHINK HOW
MOBILE AMATEUR RADIOS CONNECT TO MODERN 

VOLTAGE USING THE ORIGINAL VOLTMETER INPUT.  I DESIGNED THE RF DETECTOR FOR
A MAXIMUM 34 V PEAK ACROSS THE CAPACITOR.  THAT CORRESPONDS TO AN RF POWER
OF OR NEARLY 12 W.  THIS IS A USEFUL VALUE FOR LOW POWER OPERATIONS.  THE
PICAXE RF POWER PROGRAM SQUARES THE DECIVOLT READING, ADJUSTS DECIMAL POINT
TO READ MW, AND MULTIPLIES BY 4 TO GET MW DISSIPATED IN THE 50 LOAD RL.  I
USED THE SAME 11 LEDS AS IN THE VOLTMETER, BUT NOW THEY DISPLAY POWER
LEVELS FROM 1 TO 11 W IN 1 W STEPS.  THE LEAD PHOTO SHOWS THE LED
ARRANGEMENT ON THE ENCLOSURE.  THIS SIMPLE HARDWARE INSTRUMENT SHOWS HOW A
MICROCONTROLLER CAN BE USED TO PERFORM MEASUREMENTS, AND THE ARITHMETIC
NEEDED TO PROVIDE A MEANINGFUL INDICATION USING A BASIC PROGRAM.  MY
PROGRAM LISTING IS AVAILABLE ON THE QST IN DEPTH WEB PAGE.  AMATEUR EXTRA
CLASS OPERATOR MERT NELLIS, W0UFO, WAS FIRST LICENSED AS W9UFO IN
NASHWAULK, MINNESOTA, THEN AS W8CNC IN EAST LANSING, VIRGINIA BEFORE HE
OBTAINED HIS CURRENT CALL SIGN.  HE RECEIVED A BSEE DEGREE FROM IOWA STATE
UNIVERSITY, THEN AN MSEE FROM MICHIGAN STATE UNIVERSITY AND IS A REGISTERED
PROFESSIONAL ENGINEER IN MINNESOTA, WORKING IN MAGNETIC AND INDUSTRIAL

USE ONE DROPPING RESISTOR R7 IN COMMON WITH LEDS DS1 DS10.  THE REFERENCE
VOLTAGE FOR THE ADC IS THE REGULATED 5 V POWER SUPPLY OF THE PICAXE.
SWITCH S1 SELECTS EITHER A 9 V INTERNAL BATTERY OR THE EXTERNAL BATTERY
THAT MIGHT BE MONITORED.  WHEN MONITORING AN EXTERNAL BATTERY, THE VOLTAGE
MUST BE ABOVE ABOUT 6 1/2 V TO BE ABOVE THE OPERATING VOLTAGE OF THE 5 V
REGULATOR.  SWITCH S1 DOUBLES AS AN ON OFF SWITCH FOR THE BATTERY AND THE
GREEN LED INDICATES THAT POWER IS ON.  YOU CAN CHANGE THE MONITOR POINT
VALUES BY CHANGING NUMBERS IN THE BASIC PROGRAM.  YOU CAN PROGRAM TIGHTER
RANGES WITH CLOSER STEPS OR DIFFERENT RANGES THAT MIGHT NOT BE LINEAR.
THIS CIRCUIT MAKES AN EXCELLENT CLUB PROJECT.  STEVE ULRICH, NW0C, DESIGNED
A PRINTED CIRCUIT BOARD SO THAT MEMBERS OF THE MINNESOTA AMATEUR RADIO
TECHNICAL SOCIETY MN ARTS COULD BUILD THE MONITOR AT OUR ANNUAL BUILDERS
DAY MEETING.  THE POWER MONITOR THE POWER MONITOR PROGRAM SQUARES THE INPUT
VOLTAGE TO DISPLAY POWER.  IF THE ANALOG INPUT TO THE PICAXE IS A SINE WAVE
ACROSS A 50 LOAD LIKE RL, THE POWER IS THE SQUARE OF THE PEAK VOLTAGE
DIVIDED BY 100.  THE PICAXE CAN DO THAT WITHIN ITS LIMITS OF INTEGER
CALCULATION AND MAXIMUM WORD SIZE.  I USED A 50, 15 W, NON INDUCTIVE
RESISTOR AS AN RF LOAD, A 1N34A DIODE DETECTOR, AND A 0R01 UF CAPACITOR
FIGURE 2 TO CAPTURE THE PEAK VOLTAGE OF AN RF SINE WAVE.  I MEASURE THIS
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