RF PCB DESIGN: Cheap 20dB coupler you can design and build at home.

[@RicoElectrico]

Nice "coopler" tutorial. Thanks Hans 😁

[@venom_ftw9316]

Thank you Mr Rosenberg

[@HansRosenberg74]

You're welcome! :-)

[@TheTrueCBaer]

I checked the geometry with the (free online) Sierra Circuits Impedance Calculator which claims to be a 2D Field solver. The numbers are very close.
Without solder mask:
C=0.0979, Zodd=45.21, Zeven=55.03
S11 to S14: -42.836 ∠ 110.64, -0.287 ∠ -89.07, -20.371 ∠ 1.04, -24.244 ∠ -179.7
With solder mask (parameters guessed):
C=0.1000, Zodd=44.46, Zeven=54.34
S11 to S14: -34.881 ∠ 157.36, -0.291 ∠ -90.37, -20.191 ∠ 0.25, -24.58 ∠ -179.64

[@norbertdapunt5092]

Awesome.

[@TheTrueCBaer]

Sadly QUCS development is in such a sorry state. So much potential.