‰  NOW 40 WPM  ‰  
FOR EXAMPLE, THE TWO DIODE TYPES USED ARE NOT THE SAME PHYSICAL SIZE ONE IS
LARGER THAN THE OTHER.  THE DIODE OUTLINES PRINTED ON THE CIRCUIT BOARD ARE
ALSO DIFFERENT SIZES TO MATCH THE DIODE SIZE.  ASSEMBLING THE PC BOARD IS
STRAIGHTFORWARD THERE ARE NOT VERY MANY PARTS TO BE SOLDERED.  THIS TIME, I
DIDNT NEED ANY MAGNIFYING DEVICE TO SOLDER THE COMPONENTS.  HOWEVER, A GOOD
WIRE STRIPPER WILL SPEED THE WORK.  THE WIRES PROTRUDING FROM THE BOARD SEE
FIGURE 9 ARE CONNECTED LATER TO THE VARI

2 1/2 POUNDS.  ITS MOUNTING BRACKET USES TV TYPE U BOLTS AND WILL ACCEPT
MASTS UP TO 1 3/4 INCHES OD SEE FIGURE 7.  POWER FOR THE PREAMP IS SUPPLIED
THROUGH AN MFJ 4117 BIAS T AND 12 V WALL TRANSFORMER INCLUDED WITH THE
ANTENNA SEE FIGURE 8.  CONNECT A SHORT FEED LINE FROM YOUR RECEIVER TO THE
BIAS T, AND THEN ANOTHER FEED LINE FROM THE BIAS T TO THE ANTENNA.  AS YOU
MIGHT EXPECT, SIGNALS FROM A 3 FOOT LOOP ARE WEAK, AND QUITE A BIT OF
AMPLIFICATION IS REQUIRED TO BRING THEM UP TO USABLE LEVELS.  A SCHEMATIC
ON MFJS WEBSITE SHOWS THAT THE PREAMPLIFIER USES A PAIR OF GALI 74 MMICS
OPERATING IN PUSH PULL.  THE WEBSITE GIVES NO SPECIFICATIONS BUT SAYS THAT
THE PREAMP HAS A LOW NOISE FLOOR AND WIDE DYNAMIC RANGE.  WITH THE PREAMP
INTEGRATED INTO THE ANTENNA, WE WERE UNABLE TO TEST THAT IN THE LAB.  THE
LOOP IS SO SMALL AND LIGHT THAT IT DOESNT TAKE MUCH TO SUPPORT IT.  FOR THE
REVIEW, I USED AN OLD TV ANTENNA TRIPOD WEIGHTED DOWN WITH A COUPLE OF
CONCRETE BLOCKS AND 10 FEET OF TV ANTENNA MAST.  THAT ALLOWED ME TO ROTATE
THE ANTENNA BY HAND, ALTHOUGH IF THIS WERE A PERMANENT INSTALLATION, I
WOULD CONSIDER ADDING A LIGHT DUTY TV ANTENNA ROTATOR.  THE MAST AND
ANTENNA WEATHERED SEVERAL EARLY WINTER STORMS WITHOUT INCIDENT.  I PLACED
THE MFJ 1886 ABOUT 50 FEET AWAY FROM MY TRANSMITTING ANTENNAS AND FED IT
WITH A 75 FOOT PREASSEMBLED LENGTH OF 240UF TYPE RG 8X SIZE COAXIAL CABLE

FROM ABR INDUSTRIES.  THIS CABLE ASSEMBLY WAS VERY WELL MADE AND PACKAGED,
BY THE WAY.  THE MANUAL DOESNT MENTION PROXIMITY TO TRANSMIT ANTENNAS, BUT
SEVERAL YEARS AGO, I DAMAGED ANOTHER RECEIVE ANTENNA THAT WAS TOO CLOSE TO
MY 160 METER ANTENNA WHILE RUNNING 1,500 W, SO I AM CAUTIOUS ABOUT
PLACEMENT.  ON THE AIR IVE USED SMALL TRANSMITTING LOOP ANTENNAS BEFORE, SO
I HAD AN IDEA OF WHAT TO EXPECT.  THOSE LOOPS HAD A TUNING CAPACITOR FOR
FINDING THE BEST MATCH ON EACH BAND, WHILE THE PREAMPLIFIER IN THIS ONE IS
BROADBAND WITH NO TUNING CONTROLS.  I STARTED AT THE LOW END OF THE
SPECTRUM, TUNING AROUND THE AM BROADCAST BAND IN THE LATE AFTERNOON, AND
HEARD QUITE A FEW SIGNALS.  AS EXPECTED, ROTATING THE ANTENNA DIDNT PICK UP
A STATIONS SIGNAL LEVEL MUCH, BUT I DID FIND A VERY SHARP NULL ON GROUND
WAVE SIGNALS.  WITH CAREFUL ADJUSTMENT, I COULD TAKE A LOCAL AM BROADCAST
STATION FROM OVER S 9 DOWN TO ABOUT S 3.  ON SKYWAVE SIGNALS ON THE HIGHER
BANDS, I COULD NULL THE INCOMING SIGNALS, BUT MUCH OF THE TIME, THE EFFECT
WAS NOT AS PRONOUNCED ON THE ORDER OF 2 OR 3 S UNITS.  I ORIENTED THE
ANTENNA FOR BEST RESPONSE TO THE NORTHEAST/SOUTHWEST AND USED IT DURING THE
‰  END OF 40 WPM TEXT  ‰  QST DE W1AW  ƒ