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MICROWAVE, LENT ME A TEST 10 GIGAHERTZ TRANSVERTER WITH TWO SWITCHABLE LOS,
ONE WITH A TRADITIONAL CRYSTAL OSCILLATOR AND THE OTHER USING A SYNTHESIZER.
MDS TESTING AT THE PICNIC AND SWITCHING BACK AND FORTH SHOWED THAT THE MDS
WITH THE SYNTHESIZER WAS 2 DB LESS SENSITIVE THAN WITH THE CRYSTAL
OSCILLATOR.  LATER, I SET UP A TEST RANGE AT HOME AND GOT THE SAME RESULT TO
SHOW THAT THE EXPERIMENT COULD BE REPLICATED.  SYNTHESIZER PHASE NOISE.  THE
A32 FREQUENCY SYNTHESIZER LO USED IN THE MDS TESTS WAS ONE OF THE FIRST MADE
SPECIFICALLY FOR HAMS.  A FEW NEW TYPES HAVE BECOME AVAILABLE, SOME
SPECIFICALLY FOR LO USE, OTHERS FOR GENERAL PURPOSES WITH PUSHBUTTON OR
COMPUTER FREQUENCY SELECTION.  I MEASURED PHASE NOISE CLOSE TO THE LO
CARRIER, WHERE IT HAS THE GREATEST EFFECT ON MDS USING SOPHISTICATED
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