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EXCITER BLOCK DIAGRAM FIGURE 3 IS THE BLOCK DIAGRAM OF THE CIRCUITRY
ON THE PC BOARD.  IT IS A COMPLETE VXO SSB EXCITER ON A 2R5 X 3R8 INCH
CIRCUIT BOARD WITH 1 MW 0 DBM PEAK OUTPUT.  THE EXCITER USES THE PHASING
METHOD OF SSB GENERATION, WHICH MAKES IT EASY TO OPERATE ON DIFFERENT
FREQUENCIES.  IN A PHASING SSB EXCITER, TWO IDENTICAL SIGNALS WITH A 90
PHASE DIFFERENCE ARE GENERATED AND THEN COMBINED SO THAT ONE SIDEBAND ADDS
AND THE OTHER SUBTRACTS.  THIS METHOD IS COVERED IN DETAIL IN THE ARRL
HANDBOOK FOR RADIO COMMUNICATIONS.  THE SIGNAL QUALITY FROM THIS EXCITER IS
NOT MERELY ADEQUATE FOR THE HF AMATEUR BANDS IT IS EXCEPTIONAL.  RF
CIRCUITRY FREQUENCY GENERATOR THE FREQUENCY GENERATOR CONSISTS OF A VXO,
BUFFER AMPLIFIER AND QUADRATURE HYBRID.  IT HAS A LOT OF PARTS THREE
TRANSISTORS A VOLTAGE REGULATOR IC, A ZENER DIODE, FOUR TOROIDS AND MANY
RESISTORS AND CAPACITORS.  THERE ARE NO ADJUSTMENTS.  YOU JUST BUILD IT AND
IT WORKS.  THE FREQUENCY STABILITY IS BETTER THAN THAT OF MOST COMMERCIAL
RADIOS, EVEN WHEN PORTABLE.  VXO THERE ARE SIMPLER VXO CIRCUITS, BUT THIS
ONE IS THE BEST IVE EVER USED.  IT PROVIDES 0 DBM SINE WAVE OUTPUT, DRAWS 4
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70 NNJ KC2NFI 10 2 1 70 ENY WA5YNE 70 1 1 70 OK N0GRB 34 2 1 68 NE K9UTC 8
2 1 66 WI KI6BHB 33 2 1 66 ORG KD7HCU 13 1 1 63 WWA KP4JRS 6 1 1 62 PR
KC6WJA 5 2 1 60 LAX AD7HM 5 2 1 60 WWA KR0VER 10 1 1 60 CO KC8ZAP 5 2 1 60
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