Devlog – Day 2

Date: August 14, 2026
Time Worked: 2 hours

Today I finalized the circuit diagram for my DIY radar speed gun and continued working on the physical enclosure design.

While reviewing the electronics, I discovered that the LM386 amplifier I originally planned to use was not suitable for conditioning the CDM324’s Doppler signal for the ESP32. I researched alternatives, including the MAX9814, but ultimately decided to use an LM358 op-amp breakout board because it provides a dedicated input and can be configured to amplify the signal at 3.3V.

I then completed the full circuit diagram, including the battery, power switch, CDM324 radar sensor, LM358 amplifier, ESP32, and OLED display. I also started designing the main enclosure and planning how the horn antenna, sensor, electronics, and display will fit together in the handheld housing.

Next Steps

• Continue designing the main enclosure.
• Finalize the component placement.
• Review the wiring.