Satellite Tracker Displays The Analemma @brainwagon

Uploaded October 2011 | Updated September 2026, 4 hours ago

If you mark the position of the sun at the same time every day for a year, it traces out a figure eight called the Analemma. My tracker reproduces this effect.

555 Astable Multivibrator as an AM Transmitter

$Arduino, analogWrite, and DC voltages This morning I quickly put together a little RC filter to turn the PWM output of the Arduino into smoothly varying analog voltage to control the VCO in my G0UPL low power beacon transmitter. I think the filter is actually a bit too aggressive, it takes a significant fraction of a second to settle on the new value. Ill get a different cap in there later to speed that up a bit. (Apologies for the soft focus, Ill remember to use the macro next time).$

Hellduino: Sending Hellschreiber from an Arduino

An Arduino powered IBM PS/2 Morse Keyboard

Scrappy Introduces My Arduino/Gameduino Satellite Tracker