## The HP Half Wave 50 ohm transmission line trick

If your 50 ohm microstrip transmission line varies somewhat in impedance when you are connecting 2 50 Ohm elements together you can use a 1/2 wave length of line in between the blocks if space is available and the design is narrow band. What will happen in a full spin around Read more…

## Using WinSmith Program to Design Matching Circuit of 900MHz ISM Band Power Amplifier

WinSmith is a Smith chart match calculating program.  The starting point is 8 – j16 ohms @ 915MHz.  Both the blue and the green curves start at this point at the lower left of the curves.  Click on the image to see a bigger version What is interesting about the Read more…

## Microstrip Filling Factor versus Relative Dielectric Constant Given fixed Line Impedance

Research Links Microwaves101: Filling Factor The question arose given a fixed microstrip transmission line characteristic impedance how does the percentage of the field in the substrate change? This is called the filling factor: Keff=ER*FF+1x(1-FF) It is the fraction of the field in the substrate.  I calculated the following values: FF=(Keff-1)/(ER-1) Dk=4 Read more…