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THE BALANCED MODULATOR. SSB

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    K0YNE
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    THE BALANCED MODULATOR IS A BIG KEY TO SSB. TO MINIMIZE OR ELIMINATE THE CARRIER SUCH AS
    FM AND AM IS BLESSED WITH, THE BALANCED MODULATOR BECAME THE MEANS TO TRANSMIT A SIGNAL
    WITHOUT THE CLUMBSY AND THE WASTEFUL ENERGY OF A CARRIER.  WITH A TRANSMITTER USING
    PLATE MODULATION AND A POWER CONSUMING AUDIO MODULATING AMPLIFIER TO MODULATE THE
    PLATE VOLTAGE OF THE FINAL AMPLIFIER RF OUTPUT TUBE, THE INTELLIGIABLE SIGNAL AUDIO
    WAS PACKING A HUGE AMOUNT OF POWER IN THE CARRIER AND WASTED ENERGY.
    IN SINGLE SIDEBAND TRANSMISSIONS, NO CARRIER IS NEEDED. THE CARRIER THAT WAS LEFT BEHIND,
    CAN MERELY BE ADDED ON THE RECEIVE END WITH A BEAT FREQUENCY OSCILLATOR. THIS WAS A
    HUGE BREAK THRU ALLOWING ALL THE POWER TO BE PUT INTO THE SIDEBANDS. IT WOULD TAKE
    ABOUT 400 WATTS OF AM POWER TO EQUAL 100 WATTS OF SSB, WHEN HEARD ON THE OTHER END
    THRU THE NOISE. TRANSMITTERS COULD BE MADE SMALLER, REQUIRING LESS POWER WITH GREAT RESULTS.

    WHEN A MICROPHONE IS SPOKEN INTO, THE AUDIO IS AMPLIFIED AND SENT TO THE BALANCED MODULATOR. WHEN THE BALANCE MODULATOR RECEIVES THE AUDIO INFORMATION, IT UPSETS THE
    BALANCE OF THE MODULATOR AND ALLOWS AUDIO TO BE COUPLED INTO THE NEXT STAGE WHERE
    A SECOND IF FREQUENCY NOW ALLOWED TO COUPLE INTO OTHER STAGES AND PASSED ON THRU
    OTHER IF STAGES WHEN IT FINALLY REACHES THE TRANSMIT AND IS SENT OUT. A MORE DETAILED
    CIRCUIT OF THIS CONFIGURATION IS AVAILABLE, DENOTING EACH SECTION OF THIS REMARKABLE
    JOURNEY TOWARDS THE FINAL AMPLIFIER AND COUPLING TO THE ANTENNA.
    OFTEN , IF (INTERMEDIATE FREQUENCY) STAGES COUPLE BOTH RECEIVE AND TRANSMIT INFO.

    DOES A SSB TRANSMITTER HAVE RF OUTPUT WHILE IN TRANSMIT MODE IF NO MODULATION
    OCCURS?
    IF THE BALANCED MODULATOR RECEIVES NO AUDIO OR ENOUGH TO UPSET THE MODULATOR, THERE WILL
    BE NO RF OUTPUT. YOU CAN PROVE THIS BY OBSERVING A WATT METER WHEN TRANSMIT IS SWITCHED ON AND MIC LEVEL IS TURNED OFF. IF OUTPUT IS OBSERVED, THEN A PROBLEM EXISTS BY MICROPHONE
    CONTROL OR THE BALANCED MODULATOR IS BECOMING UNBALANCED FOR WHATEVER REASON.
    PAUL K0YNE

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