Arduino: Audio Frequency Generator abram, October 19, 2021November 23, 2022 Back in good ol’ 2012 (the year the world was supposed to end), I posted some code for a simple Arduino controlled low-frequency oscillator (LFO). It has made its way into some very interesting projects over the years, but recently I was asked in the comments if the code could… Continue Reading
Arduino: 1-Watt 2m Transmitter with RF Signal Generator abram, September 15, 2021October 19, 2021 Since I do a lot of RF projects, I wanted to see if I could make a 2m power amplifier using a minimal set of components. I have a number of BS170 MOSFET transistors that I’ve used for dozens of applications over the years from guitar pedal pre-amps to digital… Continue Reading
200 kHz Arduino Clock Generator abram, September 18, 2020October 19, 2021 Someone contacted me recently about using an ATMega328 to generate a 200 kHz clock signal for a BBD analog delay chip. I finally had a few minutes today to sit down and ensure that this code works. Varying the OCR0A value acts as a frequency adjustment on the output following… Continue Reading
7MHz Transmitter with AVR Soft-keyer abram, March 3, 2019October 19, 2021 In my last post, I went over the design of a Colpitts crystal oscillator design that put out a moderately clean 7 MHz signal. In order to match the output impedance to 50 Ω, an NPN feedback pair (at least that’s what I’m calling it) was designed. While meeting the… Continue Reading
7MHz Crystal Oscillator Design abram, February 6, 2019March 22, 2019 After constructing a 40m wire dipole that works with my SDR setup, I needed to start working on a transmission system. At the heart of virtually any RF system lies a stable oscillator, and crystal oscillators are ubiquitous in many low-power (QRP) rigs simply because they are so stable. After… Continue Reading
mellotronium 2.0: rebuild abram, August 12, 2013 after our move to Oregon two months ago, i’m finally getting back to a spot where i can do more building and experimentation. that being said, my arduino-based sampler/synth is getting a rebuild to make it more capable and road-worthy. the LED segment display is currently showing voltage out what… Continue Reading
arduino temperature TV… abram, February 25, 2013 kind of a goofy experiment, but really useful. i’ve had a lot of LM335Zs laying around for a while. my christmas present this year was a new Arduino Mega 2560 board that i’ve hardly had a chance to do anything with. using the lovely Space Tinkerer’s blog and the good… Continue Reading
Arduino: Mellotronium loops… abram, March 30, 2012March 30, 2012 a little improvisation i did after improving the LFO phase modulation and arpeggiator functions of the Mellotronium: an ATMega328P-based mirco-synthesizer. there are plenty of improvements to be made, but it’s surprising how much you can make of these microcontrollers do. combined with a Roland RC-50, it’s music composition on the… Continue Reading
Mellontronium vs. the Sun… abram, March 29, 2012March 30, 2012 the micro-synthesizer is getting fitted to draw it’s power from the sun via a 6V 200mA solar cell. it’s pretty impressive what the sun along with a cheap collection of photovoltaic cells can do. Continue Reading
ARDUINO: Setting up a Gentoo development environment… abram, March 7, 2012March 7, 2012 if you’re reading this post, most likely you’re having issues with setting up Crossdev as mentioned on the arduino.cc site. i tried countless times to configure my system for AVR compiling that way, but it always failed compiling avr-libc and would never compile avr-g++ no matter how i applied the… Continue Reading