4/10/2024 0 Comments Qucs frequency sweep tutorialIs there anything free (or that could be made free) suitable for this? To sum up for others interested in such MW mixers, what I understand the design process should be as following: 1) Choose suitable mixing diode. What I need is at least a circuit simulator capable of simulating non linear devices, like diodes. After reading a bit, I can kind of understand the design principles of the mixers. The other possibility if you don't want to simulate is just set up the basic mixer on the bench and tune it by hand. But just using the simulation software is the way to go. His books are quite academic and not too practically oriented. Steve Maas has written a lot of books about mixer design: In those, he outlines a method similar to harmonic balance that can be used to calculate impedances. Many broadband mixers aren't actually matched at all and still give relatively good performance. This page gives a list of app notes, but the links don't seem to work: Here is one on harmonic mixers (obtained by googling), seems like a typical academic paper: You might want to look at what Marki Microwave has to say about simulation: I have heard the free simulator QUCs has harmonic balance, but I have never used it: Matching is often not that important. ![]() Even if you don't have those simulators, it may be useful to look at their app notes. My experience is this gives really good results, since the only nonlinear elements are the diodes which are very easy to model. You need a harmonic balance simulator like in Keysight ADS or NI AWR Microwave office. The typical way to design a mixer is to use a simulator. I know that there are plenty of ready made 50ohm matched passive and even active mixers these days, that are very easy to implement into a design. Please understand this is more like an experiment, mainly out of my curiosity and to improve some knowledge. The proper mixer diode pair I have available is HSMS-2822 (datasheet), which I think should be sufficient. What I am after is how to guesstimate: 1) The impedance of the transmission lines to be used around the diodes 2) How to match these so the mixer will become as close to 50ohm as possible on all three ports. Those lambda/4 or lambda/2 stubs are the only things straightforward I understand there. ![]() Now that I have access to some proper test gear, I would like to give it a second chance. I have already had a go with this about two years ago, copied a design from some "schematic collection book", but the performance was really crap, totally unusable. Supposed I want to try designing a mixer for a 9cm band (3400MHz) - which is actually what I want to try. Especially, I am interested in how these things are supposed to be designed to work properly at microwave frequencies. Here is what is going on: I would like to ask, if you have any tips for literature or have a first hand experience building these. I am more interested in the microwave band use of this mixer, as at HF it is quite easier to make it work as it should. Hi! I have seen quite a lot that subharmonic diode mixers (also often called "russian mixesr" or the "Polyakov RA3AAE mixers") are quite popular in many amateur radio construction, from HF up to microwave bands.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |