Dan Koellen AI6XG
Evaluating efficiency, transformer and mismatch losses in toroid transformers - some observations.
Two methods for transformer loss are evaluated. We learn that mismatch loss must be accounted for.
Making and Hacking
Dan Koellen AI6XG
- May 16
- 6 min
Reactive Component Measurement With the NanoVNA
Exploration of using the nanoVNA to measure inductance and capacitance at frequency of use.
187 views0 comments
Dan Koellen AI6XG
- Mar 2
- 11 min
Toroid Transformers - How Hot Will It Get?
There are a number of factors in choosing a toroid for a RF transformer. While one may model electrical performance, calculate predicted...
626 views0 comments
Dan Koellen AI6XG
- Jul 20, 2021
- 9 min
Electrostatic Discharge (ESD), Does it Matter for Makers and Hackers?
Electrostatic Discharge (ESD) is a subject that can inspire a lot of discussion, head shaking and some misunderstanding. ESD damaging...
554 views0 comments
Dan Koellen AI6XG
- Jun 16, 2021
- 13 min
Don't Fear the Smith Chart
Like many radio amateurs I was initially intimidated by the Smith chart. Transmission line and antenna theory, unfamiliar terms and...
727 views0 comments
Dan Koellen AI6XG
- Apr 25, 2021
- 9 min
How I Killed a Microcontroller
This blog outlines the steps taken to determine why a microcontroller no longer works, and the journey to find the damage on the chip.
180 views0 comments
Dan Koellen AI6XG
- Jan 25, 2021
- 2 min
The Digi-Disco, a 1970's Light Controller
This is a light system that I designed and built in 1978 to control large flood lights of different colors, synchronized to disco music...
93 views1 comment
Dan Koellen AI6XG
- Nov 23, 2020
- 1 min
Wishing You a Very Random Christmas
Being the holiday season I decided to post this article from the December 2014 issue of Nuts & Volts magazine www.nutsvolts.com that I...
51 views0 comments
Dan Koellen AI6XG
- Jun 29, 2020
- 7 min
Big Font Clock Update: Dimmer-Interface PCB and Setup Instructions.
A prior post described the development and build of a clock to display time and date for UTC and Local. The clock characters are large,...
151 views0 comments
Dan Koellen AI6XG
- Apr 5, 2020
- 3 min
Auto Run for your Raspberry Pi - how to have your Rpi boot up in the desired configuration.
The Raspberry Pi (Rpi) is a great single board computer (SBC) that can be used in many projects and comes in different configurations. I...
59 views0 comments
Dan Koellen AI6XG
- Feb 9, 2020
- 9 min
Big Font Clock - Relieve for Old Eyes
Recently the Maker Space that I frequent received a number of 4 line 40 character (4 x 40) LCD displays. They asked me to figure out how...
430 views0 comments
