‰  NOW 35 WPM  ‰  TEXT IS FROM MAY 2018 QST  PAGE 36‰

DEVICE TEST  THE DEVICE SHOWN IN FIGURE 3 WAS CONSTRUCTED AND ITS
MICROCOMPUTER PROGRAMMED, AND A 146 MHZ MEZZANINE RF FILTER BOARD WAS
INSTALLED.  WITH THE DEVICE TURNED ON, AND WITH NO ANTENNA ATTACHED TO THE
RF INPUT CONNECTOR, THE ANALOG DBM METER READS ABOUT 0R3 V, CORRESPONDING
TO A BACKGROUND LEVEL OF 72 DBM.  R7 AND R8 WERE ADJUSTED SO THAT THE METER
READING CORRESPONDS TO THE ACTUAL VOLTAGE MEASURED OUT OF PIN 4 OF THE
AD8307.  A POWER LEVEL OF 72 DBM IS ABOUT THE LOWER LIMIT OF RF DETECTION
BY THE AD8307 LOG AMPLIFIER.  THE DEVICE TICKS AND THE LED BLINKS EVERY
SECOND.  OTHER USES CONSIDER ADDING A SUBSYSTEM LIKE THE REMOTE RF LEVEL
ANNUNCIATOR TO YOUR CURRENT REPEATER IN ORDER TO SEND THE SIGNAL STRENGTH
OF A RECEIVED SIGNAL BACK TO AN OPERATOR USING THE REPEATER FOR HANDHELD
TRANSCEIVER OR ANTENNA TESTING.  THIS COULD BE A 1 MINUTE TEST OPTION THAT
IS PRE ACTIVATED BY A TOUCH TONE.  WHEN A 2 METER RUBBER DUCKIE ANTENNA IS
ATTACHED TO THE DEVICE, THE ANALOG METER READS ABOUT 0R6 V.  AN RF
THRESHOLD JUMPER IS INSTALLED AT THE 52 DBM POSITION TO KEEP LOCAL RF
SIGNALS BELOW THAT FROM TRIGGERING ANNOUNCEMENTS.  WHEN A 50 MW FM 146 MHZ
SIGNAL IS TRANSMITTED FROM A HANDHELD TRANSCEIVER HELD 2 FEET AWAY FROM THE
DEVICE, THE METER READS 1R8 V AND DEVICE ANNOUNCES 10 DBM USING TWO MORSE
CODE CHARACTERS FROM ITS SPEAKER AFTER THE CARRIER DROPS.  THE INSERTION
‰  END OF 35 WPM TEXT  ‰  QST DE W1AW  ƒ