=  NOW 30 WPM  =  TEXT IS FROM FEBRUARY 2022  QST  PAGE 94 =

TO FM OR SSB.  THE GLOBE SCOUT USED A TECHNIQUE CALLED HEISING MODULATION,
WHICH INVOLVED USING AN ORDINARY IRON POWER SUPPLY TYPE CHOKE TO DECOUPLE
THE DC POWER SUPPLY FROM THE MODULATOR, THEREBY FEEDING THE FINAL TUBE WITH
MODULATED PLATE VOLTAGE SEE FIGURE 3.  THIS WORKED, BUT YOU COULD NEVER
ACHIEVE FULL MODULATION, AND BECAUSE HEISING MODULATION WAS GENERALLY USED
FOR ECONOMIC REASONS, THE REST OF THE AUDIO CHAIN WAS GENERALLY COMPROMISED
AS WELL.  OTHER RADIOS OF THE TIME USED SCREEN MODULATION, WHICH GENERATED
AM BY MODULATING THE SCREEN GRID OF THE FINAL AMPLIFIER.  WHILE SCREEN
MODULATION WORKED AND WAS CERTAINLY COST EFFECTIVE, THE JOHNSON RANGER WAS
BY FAR THE BEST SOUNDING WITH ITS PUSH PULL 6L6S AS THE AUDIO MODULATOR AND
A REAL MODULATION TRANSFORMER, BUT IT COST THREE TIMES MORE THAN THE GLOBE
SCOUT.  GLOBE SCOUTS WERE ALSO CATHODE KEYED, WHICH WAS AN EASY AND
PRACTICAL METHOD OF KEYING THE RADIO IN CW.  HOWEVER, IT COULD BE
DANGEROUS, AS IT PUT SEVERAL HUNDRED VOLTS ACROSS THE KEY TERMINALS.  I
LEARNED THIS THE HARD WAY, DURING MY FIRST CONTACT USING A USED GLOBE
SCOUT.  OTHER RADIOS, SUCH AS THE JOHNSON RANGER, HAD GRID BLOCK KEYING,
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