my recent reads..

LEAP#283 XOR with NAND gates

I recently needed an XOR gate, but only had NAND gates on hand. NAND (and NOR) gates are sometimes known as “universal” logic elements, as it is possible to contruct any other type of logic gate with them. So while a little wasteful, I’m using the four NAND gates of a single 74LS132 chip to produce one XOR gate. As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub hero_image


read more and comment..

LEAP#282 Function Generator Kit

The XR-2206 monolithic function generator is a pretty capable chip that can do a whole lot more than is required for this function generator kit (like sweep and AM/FM synthesis). The part now appears to be obsolete however, which probably explains why it is showing up in a flood of kits similar to this one. Performance is remarkably good. The main drawback is no feedback or calibration of actual frequency and amplitude being generated. If the details matter, it is necessary to also hookup an oscilloscope or frequency counter. Of course this also means there’s no warning or protection against clipping the output signal. As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub hero_image


read more and comment..

LEAP#281 Three-stage FM Transmitter

The dazaro3 Youtube channel has some of the simplest and most practical FM transmitter circuits around, with a bonus that he actually shows them working. I first experimented with his three-stage transmitter on a breadboard (LEAP#280) and got such good results that I then put it in an Altoids can, and finally bought a legit one from dazaro as a benchmark and a bit of payback for sharing such great designs. As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub hero_image


read more and comment..

LEAP#279 Single-stage FM Transmitter Kit #2

I picked up another FM transmitter kit because it was too cheap to ignore. Initially transmitting slightly high on the FM band, some adjustments of the LC tank got it down to working quite decently around 92MHz. As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub hero_image


read more and comment..