This is the page of projects, most of which related to radio receiver and transmitter. In addition to oldie goodie stuff, I will also include up-to-date projects, for instance, Arduino, LoRa / Meshtastic matters.
An Easy-to-build Active Small Loop Antenna for Urban Indoor MW/SW Reception
Motivation I am living in a downtown apartment where an outdoor “large” antenna is impractical. My only feasible location for a fixed antenna is at the balcony. Obviously for SWL-ing at frequency below ~15MHz, only electrically small 1 antennas can be used. Moreover man-made noise is very high in my area, rendering a whip antenna…
A low cost comb generator for frequency synthesis applicartions
Introduction A comb generator is a simple but useful piece of equipment. Most comb-generators rely on a Step-recovery-diode (SRD) to create very narrow pulses which are rich in harmonics. Unfortunately step recovery diodes are expensive and very fragile (easily damaged by ESD). Now they are hard to find. This post shows one low-cost alternative design…
From Hobby to Professional 