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OUT IN ORDER TO SEE MORE OR LESS DETAIL FROM THE SCAN.  WITH ITS CONSTANT,
STABLE OUTPUT, THE AA 2000 ZOOM IS SUITABLE FOR RECEIVER SENSITIVITY
TESTING WHEN USED WITH A GOOD STEP ATTENUATOR, KEEPING IN MIND THAT THE
OUTPUT WAVEFORM IS A SQUARE WAVE WITH MULTIPLE HARMONICS.  THE AA 2000 ZOOM
CAN ZERO OUT A TRANSMISSION LINE FOR MAKING ACCURATE REMOTE ANTENNA FEED
POINT IMPEDANCE MEASUREMENTS IF OPEN/ SOURCE/ LOAD CALIBRATION STANDARDS
ARE AVAILABLE.  OTHER USEFUL FEATURES AVAILABLE IN THE AA 2000 ZOOM INCLUDE
THE ABILITY TO MEASURE CABLE LENGTH, CABLE LOSS, VELOCITY FACTOR, AND
CHARACTERISTIC IMPEDANCE.  THE TDR FUNCTION IS USEFUL FOR FINDING
DISCONTINUITIES IN YOUR ANTENNA SYSTEM.  ONE USE FOR THIS IS TO DETERMINE
THE PHYSICAL LENGTH OF COAX TO ANY OF YOUR ANTENNAS, JUST BY LEAVING THE
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