Linux Mint, QRP, & C / C++ Compilers

 Greetings:

On the bench I'm studying PLL techniques using a sample & hold detector + VHF circuitry. Currently, I've got nothing to post RF-wise. Another factor includes changing my personal computer to a 100% Linux machine. Although I built a new PC + installed Windows 11 for my wife — I decided to go the Linux route for myself.  Why? Lots of reasons, but mostly preference. 

I'm not a gamer, music producer, nor multimedia tech developer so no compelling reasons exist for me to just run Windows. Linux has its own set of problems and certainly since switching over my computer knowledge has grown immensely.  Linux seems to suffer a lack of up-to-date documentation. Most of the programs were written for free and some unpaid code writers feel loathe to write/update their documentation in plain language.

I chose Linux Mint with the desktop interface, Cinnamon. All my hardware worked perfectly right away. I also enjoy the role of the terminal in Linux . With 8 fingers + 2 thumbs, I type faster than clicking a mouse.  (The terminal is a text input and output environment which also exists in Windows). Back in 1984, I knew most of the DOS commands & their switches ( I still do), plus advanced batch file techniques and taught them to folks for cash. I've always enjoyed working on terminals and automating tasks.

For radio and electronic software , a lot of good applications are hosted on web pages, however, many needed applications are not. Thus, I've been writing code — mostly in C. And yes, for the console.  Most of the time,  I tend to need software to quickly analyze circuitry I see in service manuals.  I'm trying not to use any Windows programs.

My first application served as trial run and involves a voltage feedback amplifier used in a lot in VHF gear for boosting small signals:

Above — Amplifier A runs voltage feedback. Sometimes designers employ an emitter resistor with or without AC bypass. In figures B and C, the amp gets set up in Hybrid-H parameter mode for small signal analysis. I feel very fortunate to have received introductory teaching of 2-port network analysis by Wes, W7ZOI.  He instructed me in both scattering  S-parameter techniques & linear circuit analysis using H- parameters. As a builder, simply do what you can:  hand-calculator calculations — or full on simulations in SPICE. 

Another option is to write programs to run the equations and give you the information you seek. Small signal analysis is often boring and perhaps unhelpful for non-engineers.

However, you can write programs to calculate almost anything - such as inductance for X turns of wire on a toroid core such as the T50-6. This hobby is more than making circuits. For some, measurement + design work & tool use serves as equal sources of pleasure to actually just making circuits on your bench.

Above — A screen shot of my console screen where I compile vFBA.c, (my source code) into the executable file ap2 --- and then run the app with the command ./ap2 . After that the terminal asks for and receives 4 parameters including the value of any emitter resistor.  Then the application calculates and gives me the 6 things I want to know when I am viewing this type of transistor circuit in a service manual/schematic. I wrote many apps for different type of amplifiers + other circuits and keep track of them with a cheat sheet.  I only re-compile the C program if I change something in the code.

This allows rapid program development as you do not waste time on GUI code and also don't bother writing tons of error checking code which is typically needed for applications that get public use. I like that all I need is a text editor -- and that the C /  C++ compiler is built into the shell on my terminal.

I feel surprised about the number of great open-source applications available for free:

Above — The program I use to edit RAW image files and render them into jpgs. The jpeg rendering engine does a great job. The program is called RawTherapee 5.1. Kudos to the designers.

Finally, in the past , I made my schematics with the Windows Paint program.  I desperately sought an equivalent program.

Above — I settled on a program called KolourPaint. Because I've used Paint for decades, it took some time to adjust. I miss a couple of familiar routines, however, KolourPaint also has some capabilities that Paint does not have.  I think it will work out fine as I gain experience with this app.

Best to you!