As a newbie here can I recommend an old but powerful little program 'RFsim99'
http://www.sandiego.edu/~ekim/e194rfs01/RFSim99.exe
Works with windows 98 to XP (and Wine under Linux).
Plots impedance of networks on the Smith charts, calculates matching networks, filters and much more..
For the quarter wave stub see the attachments below.
(Ignore the 1Gohm resistor, like most simulators, something must be connected to every node to avoid an error message.)
50cm of coax with a velocity factor of 0.67 (200/300 m/sec) is a quarter wavelength at 100MHz.
At this frequency, if one end is open circuit, it will look like a short circuit at the other creating a notch as you remembered.
Jim
ps This is my first post on the forum so please forgive any problems with the attachments.
http://www.sandiego.edu/~ekim/e194rfs01/RFSim99.exe
Works with windows 98 to XP (and Wine under Linux).
Plots impedance of networks on the Smith charts, calculates matching networks, filters and much more..
For the quarter wave stub see the attachments below.
(Ignore the 1Gohm resistor, like most simulators, something must be connected to every node to avoid an error message.)
50cm of coax with a velocity factor of 0.67 (200/300 m/sec) is a quarter wavelength at 100MHz.
At this frequency, if one end is open circuit, it will look like a short circuit at the other creating a notch as you remembered.
Jim
ps This is my first post on the forum so please forgive any problems with the attachments.
