Products

I wanted to replace the drifty VFO in one of my rigs with a digital solution, but my hand-wired solution was messy, fiddly, and prone to ground loops and digital noise. So I designed a PCB ...
More Info

The performance of a receiver or transmitter depends on careful impedance matching between its sub-systems: its mixers, filters, and amplifiers. Mismatches can cause loss of signal strength, inter-modulation ...
More Info

Adding automatic gain control to a TIA IF amp makes the audio volume of a receiver as predictable as the impedance of the amp itself. AGC keeps strong signals from blasting-out your eardrums ...
More Info

Dual-gate MOSFETs were once common in Ham radio designs, but no through-hole versions are now available on the market. These little half-inch breakout-boards with pre-soldered SMD versions might make ...
More Info

The operational amplifier–the "op-amp"–was created to do by analog means what we now do digitally: to simulate mathematical operations. In application, though, op-amps have long been used for so-much more ...
More Info

A clean, ripple-free and narrow-skirted "xtal" filter is essential for excellent performance, especially in a receiver. They are, however, among the most difficult builds for a home-brewing amateur to pull off ...
More Info

Stop caring how many I/O pins your Arduino or other micro-controller has. Use the I2C two-wire bus and you can have an digital display, an Si5351, a number of other useful devices, and now a rotary ...
More Info

COMING SOON! A general purpose, discrete-component audio amplifier with selectable three or four preamp stages. Based on a design by Richard Anderson, KE3IJ (SK) ...
More Info

COMING SOON! A hybrid-cascode ("hycas") IF amplifier with AGC (IF-based). Based on a design by Wes Hayward W7ZOI and Jeff Damm WA7MLH ...
More Info