‰  NOW 25 WPM  ‰  TEXT IS FROM DECEMBER 2008 QST  PAGES 62, 63 AND 75  ‰

MILLIVOLTS AT FREQUENCIES UP TO 50 MHZ OR HIGHER WILL DO.  YOULL ALSO NEED
AN OSCILLOSCOPE WITH A BANDWIDTH OF AT LEAST 20 MHZ.  TO CONNECT THE SIGNAL
SOURCE TO THE CIRCUIT, FIND A 2 TO 3 FOOT PIECE OF COAXIAL CABLE WITH A
CONNECTOR ON ONE END.  ATTACH A PAIR OF ALLIGATOR CLIPS TO THE END WITHOUT
THE CONNECTOR, OR JUST SOLDER THE BRAID AND CENTER CONDUCTOR TO SHORT
PIECES OF WIRE THAT CAN BE PLUGGED INTO THE BREADBOARD.  SET THE SOURCE TO
ABOUT 1 MHZ AND CONNECT IT TO THE FILTER.  USE THE SCOPE TO MEASURE THE
FILTER INPUT AND OUTPUT SIGNALS IN VP P.  INCREASE THE SOURCE FREQUENCY
UNTIL THE OUTPUT VOLTAGE, VOUT 0.  707 VIN.  THIS IS THE FILTERS CUTOFF
FREQUENCY, F0, AND IT SHOULD BE SOMEWHERE ABOVE 20 MHZ AND LESS THAN 35
MHZ.  IF YOU HAVE A SCOPE WITH A BANDWIDTH OF 20 MHZ OR LESS, YOU CAN STILL
USE IT IF IT CAN PROVIDE AN INDICATION, BECAUSE WE ARE TAKING RELATIVE
‰  FROM PAGE 75  ‰
1,660 MI New River Valley ARC N4NRV 291 2 18 1,632 VA Golden Triangle ARC
‰  END OF 25 WPM TEXT  ‰  QST DE W1AW  ƒ