SDRs have been a game changer for radio hobbyists, but for ham radio applications, they often need a little help. That’s especially true of SDR dongles, which don’t have a lot of selectivity in the HF ...

Many sensors have a small analog signal that rides on top of a larger dc pedestal. For these circuits (Fig. 1), the signal must be ac coupled and amplified before it’s digitized. The feedback of an ...

Setting out to design a higher order, high pass filter using the Sallen-Key single op amp topology will immediately run into a question of required amplifier bandwidth. This is most often set by the ...

Salisbury, MD. K&L Microwave announced it has developed a family of miniature high-pass filters with cutoff frequencies of 6 to 18 GHz. The filters guarantee rejection of 45 dB at 1/2 the 3-dB cutoff ...