Engineering blog

Engineering Notes

Practical RF and radar design notes: radomes, waveguides, antennas, cables and machining, with the numbers behind each choice.

Read a series

Series · 14 chapters · 4 partsRF Bench BasicsHands-on RF for the bench: attenuators, coax loss, connectors, filters, DC blocks and bias tees, 50 ohm matching, power dividers and waveguide, each with the datasheet numbers that matter and a short video.Start with Chapter 1 →Series page →
All 14 chapters

Part A · Levels, cables and connectors

  1. 1RF Attenuators Explained: dB, Pi and T Pads, and Return Loss
  2. 2Coax Cable Loss vs Frequency: What Your SDR Cable Costs You
  3. 3SMA vs RP-SMA vs BNC vs N: Choosing the Right RF Adapter
  4. 4ESP32 External Antenna: U.FL to SMA Done Right

Part B · Filters, DC and matching

  1. 5SDR Filters Explained: Low-Pass, Band-Pass and Band-Stop
  2. 6DC Block and Bias Tee Explained: DC and RF on One Coax
  3. 750 Ohm, VSWR and Return Loss Explained (and What a Load Does)
  4. 8RF Power Dividers and Combiners Explained: How a Wilkinson Works

Part C · Waveguide and mmWave parts

  1. 9Waveguide Explained: Cutoff Frequency, TE10 and WR Sizes
  2. 10Machined or Metallized Plastic? How Waveguide Antennas and Horns Are Built, 10 to 300 GHz
  3. 11Wavelength, Machining Tolerance and Test Cost: Why mmWave Parts Get Expensive

Part D · Bench recipes

  1. 12SMA Attenuator to Protect a Spectrum Analyzer or SDR Input
  2. 13NanoVNA Accessories: Cables, Adapters and Pads You Need
  3. 14How to Power a GPS Antenna, LNA or LNB with a Bias Tee
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