Another Linux user open wound: For ages I have been stuck without proper circuit simulation in Linux. I don’t define myself a power-user (only as a super user, but only when I run sudo) as I run Ubuntu, but that…
Category: QUCS
The Perils of Port Extensions
This post concerns a much more simplified version of the previous one. Last time we dealt with an arbitrary length line, with an unknown characteristic impedance. For that matter, a double length line de-embedding structure was suggested. In this post,…
De-Embedding 2 Whole Degrees of Freedom
In the last post we discussed de-embedding a simple transmission line, namely a phase shifter and attenuator. Surprisingly, most structure that we might need to de-embed will be far from that, to say the least. To maintain a methodical approach,…
Basic De-Embedding, 1st Order Model
It occurred to me recently that although I named this site RF with care (for reasons I definitely cannot recall any more), I have not really written here anything RF or EM related in any way. So to start it…
Just a bit about amplifiers
Following the previous post, this post will mostly discuss how amplifiers work and just a few words about class-D amplifiers. The software of choice, for the schematic work, was KiCad. This was just because of some arbitrary roam on the…
Variable resistors in QUCS
While designing a 3-band equalizer, using QUCS (view previous post about QUCS here), the need for variable resisors came up. As the current versions of QUCS still don’t support EVALUE components, it was impossible to implement voltage controlled resistors (i.e.…