# kicad KiCad is a free, open-source electronics design automation suite for schematic capture, integrated circuit simulation, PCB layout, 3D rendering, and data export. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## Understanding RF Trace Impedance in a KiCad Sensor Hub PCB DevFeed: [Understanding RF Trace Impedance in a KiCad Sensor Hub PCB]() Original publisher: [Read original article]() Published: 2026-09-10T03:45:45Z Content type: article Language: en Sources: [Jessie Frazelle]() Topics: [Hardware](), [kicad](), [codex]() Tags: [codex](), [hardware](), [kicad](), [pcb]() ### AI overview The article explains how the author resolved differing impedance calculations for a Sensor Hub's RF layout. It shows that both inner PCB layers contained ground copper, and that the RF trace's reference plane, dielectric thickness, copper thickness, and adjacent ground gap affect the 50-ohm impedance calculation. ### Source excerpt We're back! Not with rework. This time we're talking about impedance and review. Apparently I can get into a heated argument about a board before it even gets here. In part one, I wrote about using Codex to design my own hardware because I'm sick of Control4, Savant, and the rest of that shit. The useful part wasn't one-shotting a PCB. It was having the agent work through datasheets, compare parts, and check the design. Then I had to notice that the connectors were facing the wrong fucking way. There was more to review. Which board are we arguing about? I was talking through the Sensor Hub's RF layout with Paul, and we were getting different answers for the impedance. This turned into a pretty heated argument, which might have scared some of the other people in the room. Honestly, we were just trying to figure it out. Paul started with this impedance calculator. I kept annoying him because I still didn't understand why we were getting different numbers. Eventually he switched to JLC's calculator, which was what the model was using. I wanted to understand the model's math and compare it with his. The KiCad view was part of the confusion. The connection looked orange, and the second interior layer, In2.Cu, was orange in the layer list. The first interior layer, In1.Cu, was green. So we thought ground was on the second one, and kept arguing about the thickness between layers. Then I realized both interior layers had ground copper, with ground vias connecting across layers. Seeing orange didn't mean the connection was only on that layer. There was ground on the green layer too, right under the RF trace. The model was right! I was just trying to understand what it was telling me. The confusing view, recreated in KiCad. In2.Cu is selected in orange; the green In1.Cu ground is there too. The RF trace is on F.Cu, the top layer. There is 0.1164 mm of insulating material between it and the first inner ground plane. If we used the second inner layer as the reference, we'd be i ## esp32pin.com: Interactive ESP32 Pinout Reference DevFeed: [esp32pin.com: Interactive ESP32 Pinout Reference]() Original publisher: [Read original article]() Author: John Lee Published: 2026-08-06T00:00:00Z Content type: article Language: en Sources: [Blog on Developer Portal]() Topics: [ESP32](), [kicad](), [Espressif]() Tags: [blog](), [community-contribution](), [development-board](), [esp32](), [gpio](), [kicad](), [open-source](), [pinout]() ### AI overview esp32pin.com is a free, open-source interactive pinout reference for the ESP32 family. It identifies pin constraints such as strapping-pin behavior, ADC2 conflicts with Wi-Fi, flash-pin restrictions, input-only pins, and USB or JTAG warnings. ### Source excerpt esp32pin.com is a free interactive pinout reference for the ESP32 family. Every pin carries its real-world constraints, the data is generated from Espressif's official KiCad libraries and cross-validated against the esp-gpio-tool dataset, and new dev boards can be proposed right in the browser. ## How we turned the Replay keynote surprise into an open-source embedded playground DevFeed: [How we turned the Replay keynote surprise into an open-source embedded playground]() Original publisher: [Read original article]() Author: Shy Ruparel Published: 2026-05-26T00:00:00Z Content type: article Language: en Sources: [Temporal Blog]() Topics: [Open Source](), [Embedded Systems](), [ESP32-S3](), [MicroPython](), [kicad]() Tags: [embedded](), [embedded-systems](), [esp32-s3](), [kicad](), [micropython](), [open-hardware](), [open-source](), [temporal-voices]() ### AI overview Temporal describes how it designed and distributed 2,000 hackable ESP32-S3 badges at Replay and then released the badge's firmware, hardware designs, fabrication files, documentation, tools, examples, and community app infrastructure as an open-source ecosystem. ### Source excerpt We handed out 2,000 tiny hackable computers at Replay. Now the whole ecosystem is open source. Here's the story of how we built and shipped them.