I've been building and flying electric R/C model airplanes since 1994, starting with an electric conversion of a Goldberg Gentle Lady. I currently fly my partial-own-design Fred's Super Special and a twin-electric conversion of a Sig LT-25.

As an inveterate tinkerer, I've designed and built a lot of my own support equipment, such as electronic speed controls and NiCd chargers. From 1997 to 2004, I wrote for Quiet Flyer magazine. I also developed MotoCalc, the popular program for choosing and optimizing electric model airplane power systems.

Stefan's Electric R/C Web Site contains many of my articles about various projects, model planes, R/C events, and aerial photography. I'm adding new articles regularly, so check back often.

After flying models for years, I got the itch to try the "real thing". I started pilot training in 2001 and got my license in 2002. Since then, I've averaged about 50 hours a year in Cessnas and Diamond DA20-A1 Katanas.

During that time, I've had a lot of ideas about flying, which I'm writing down at Stefan's General Aviation Web Site. Since flying also provides some interesting photo opportunities, you'll find quite a few pictures there too.

Combining my R/C model building experience with my desire to have my own plane, I'm now in the process of building a single-seat, all-wood Evans VP-1 Volksplane.

Lead-Acid Field Battery Care

Computer Controlled Battery Manager

Whiz Wheels: E6-B versus CR

Cessna and Diamond Checklists

As an avid electric R/C enthusiast and a professional mathematical software developer, it didn't take long to put the two together to start developing MotoCalc, the most versatile and easy to use R/C electric flight power system selection and prediction program available.

MotoCalc tells you everything you need to know: Amps, Volts, Watts, RPM, Thrust, Rate of Climb, and more. It can suggest power systems for your model, provide detailed performance predictions for any set-up you choose, and explain its results in plain English.

Visit www.MotoCalc.com to learn more >>

When my trusty HP-42S calculator began having troubles, I set out to find a replacement and was surprised to find that HP no longer made a comparable RPN calculator. Fortunately, a colleague gave me his retired HP-19C, and HP-41CX, both of which needed only minor repairs.

I soon discovered that there was an active used HP calculator market, and I casually started collecting them. After a while I became interested in slide rules too, and have built up a small collection of those as well.

Stefan's Historical Computing Devices web site showcases my collection, and contains articles of interest to fellow calculator and slide rule collectors.

My first hobby was electronics, starting with a Radio Shack® 150-in-1 lab kit and working my way up from there. I have no formal training in the field, but I've learned a lot from reading and experimenting, my father, and my biggest influence and mentor, Mark Tilden during my days at the University of Waterloo.

These days, I use my electronic skills primarily in pursuit of my other hobbies, or to make life easier on our horse farm.

Stefan's Electronics Web Site is a repository of projects I've built and documented, most of them with complete construction details. There are also reviews of various bits of electronic equipment I've bought and liked.

HP-19C Programmable Calculator

A Matrix Multi-Tool for the HP 35s

Review: Sanyo's USB NiMH Charger

Computer Controlled Battery Manager