Resources and Tools for our Viewers

Summary List of Tools 

1.  Web Links
2.  Our Make a Frequency Stable L-C VFO notes from 2014 - 2024
3.  Our Gilbert Cell Mixer notes from 2023
4.  Our old x86 Windows GUI NPN Bias application
5.  Gilbert Cell Mixer MAX268X series:: FDIM 2025 - Jason, NT7S video
6.  SRF of Common Bypass Caps + What do I use for 3.5MHz or even 1.8 MHz?
 

1.  Web Links

Marki Microwave LC Filter Design Tool
W7ZOI Website
Iulian YO3DAC-VA3IUL's web site 
Steve, VE7SL's blog

Bettina Neumryr  Popular Youtube Channel - building circuits from old magazines
Applied Etherifcs -- NT7S on Substack 

2. Our Make a Frequency Stable L-C VFO notes from 2014 - 2024

The notes = a 6 page pdf file. Mostly discusses the temperature coefficent of VFO parts to hopefully help builders get a little more frequency stability if they choose to make an ancient/vintage Inductor + Capacitor (L-C) Variable Frequency Oscillator.  

Click to download LC-VFO-Notes.pdf

3. Our Gilbert Cell Mixer notes from 2023

By request. Happily, we kept a draft text document of Part 1 of our former blog post that got about 7K views per month in 2023. This version lacks my minor edits-over-time + nicer 'Blogger' formatting -- and Part 2.  Part 2 featured some example-concept, discrete BJT mixer designs. The file notes = a 16 page pdf document of my raw notes with figures. These notes were even referenced in a successful doctoral thesis by an Asian PhD scholar.  

Click to download GilbertCell.pdf 

4. Our old x86 Windows GUI NPN Bias application

Click to download nbias.zip

 

Above — A screen-shot of the Bash version of NPN-bias running in the terminal. I work on it from time to time -- and plan to add some AC small-signal analysis.

5. Gilbert Cell Mixer MAX268X series:: FDIM 2025 - Jason, NT7S video

 

6. SRF of Common Bypass Caps + What do I use for 3.5MHz or even 1.8 MHz?