Samwise Makers' News
Thursday, September 3, 2026
Namib Desert Field Test Reveals Corrosion Challenge for Electrostatic Fog Harvester
The Plasma Channel team, working with researchers from the University of Namibia, completed a field test of a solar-powered electrostatic precipitation fog harvester in the Namib Desert. The device uses high-voltage electrodes to charge and collect airborne fog droplets, but the test revealed a critical problem: salt from Atlantic Ocean coastal air corroded the high-voltage electronics. The coastal Namib's persistent salt-laden fog accelerated degradation of metal components in ways not anticipated during laboratory testing. With collection efficiency data in hand, the team is now redesigning the electronics for corrosion resistance ahead of a planned follow-up test in Chile's Atacama Desert.
Switch Mod Fixes Hall Effect Sensor Problem in Citroën Door Logo Projector
A maker known online as OrangeTungsten modified the door-opening logo projector in their Citroën to fix a chronic Hall effect sensor failure. The projector casts the car's badge logo on the ground when the door opens, and originally used a Hall effect sensor to detect door movement, but the trigger magnet repeatedly fell off in use. Disassembly revealed an 8-pin microcontroller inside that simply polls the Hall effect sensor and switches a transistor to power the LED array. OrangeTungsten replaced the sensor with a direct button switch, eliminating the magnet entirely. The complete modification is documented in a GitHub repository.
FPGA Board Brings HDMI Output to TRS-80 Color Computer 2 with Audio over Single Cable
Scott Baker built an FPGA-based HDMI output adapter for the TRS-80 Color Computer 2 after finding the commercial CoCoVGA and CoCoDV solutions sold out and unavailable. Using a Tang Nano board with a Gowin GW1N-1 FPGA, the design taps the digital signal lines feeding the MC6847 video IC and reconstructs the video output as an HDMI stream. Level shifters bridge the voltage difference between the vintage 5V logic and the FPGA inputs. An on-board ADC captures the CoCo2's analog audio and transmits it over the same HDMI cable. Baker published the full design for other Color Computer owners facing modern display compatibility problems.
1970s Sears Calculator Doubled Thermal Print Resolution by Physically Oscillating the Print Head
A teardown and analysis of a 1970s Sears 12 scientific calculator by the Danalog YouTube channel found that the device doubles its thermal printer resolution through a mechanical trick: the entire print head assembly physically oscillates sideways during printing. The calculator uses a Mitsubishi M58671 thermal IC to drive the print head. By oscillating the head horizontally during each print pass, it effectively doubles the number of addressable dot positions compared to fixed-head designs such as the Texas Instruments TI-5015. The technique was a cost-effective engineering solution allowing higher print resolution without increasing the number of heating elements in the thermal print head.
ZX81 16K RAM Pack Teardown Reveals 4116 DRAM Circuitry and Self-Oscillating Power Supply
[Happy Little Diodes] opened a ZX81 16K RAM expansion pack to find far more circuitry than expected inside the slim plastic housing. The ZX81 originally shipped with just 1K of RAM, and this popular upgrade contains two PCBs connected by ribbon cable: one carrying 74-series logic chips and the other holding 4116 DRAM chips and a discrete power circuit. The 4116 requires both +12V and −5V supplies, which the board generates internally using a self-oscillating single-transistor switcher with a Zener diode regulator and quench diode. The article also notes the expansion's notorious instability: the slightest movement while connected could trigger a full system reset.
Reverse Polish Notation Calculators Survive in 2026 via New Hardware, DIY Builds, and Software
A Hackaday feature examines the current state of Reverse Polish Notation calculators, first popularized by Hewlett-Packard for scientific computing. RPN, whose mathematical foundations were developed by Polish logician Jan Łukasiewicz, places operators after their operands — A B + rather than A + B — eliminating the need for parentheses and enabling efficient stack-based computation. HP later exited the calculator market, licensing its line to Moravia Consulting, while older models such as the HP-15C, 16C, 32S, 42S, and 48 have become sought-after collectibles. The article surveys remaining options: new hardware still in production, DIY calculator builds, and software implementations for computers and smartphones.
ESP32-P4 Weather Station Monitors PM2.5, NOx, VOC, CO2 and Presence via 24 GHz Radar
Harald Kreuzer published a build log for a DIY weather station and air quality monitor built on the Waveshare ESP32-P4-Module-DEV-KIT-C. The station pairs an ESP32-P4 with a 10.1-inch 1280×800 IPS display and a Sensirion SEN66 sensor measuring PM1.0, PM2.5, PM4.0, PM10, NOx, VOC, and CO2 levels. A BH1750 light sensor and DFRobot C4001 24 GHz mmWave radar add light measurement and presence detection. Remote sensor nodes communicate via LoRa using a Heltec V4 module and ESP-NOW. The firmware stack uses ESP-IDF with LVGL and EEZ Studio for the display interface. Full source code is on GitHub at HarryVienna/ESP32-Weather-Station-and-Air-Quality-Monitor.
Sources: CNX Software
Top Crowdfunding
Kickstarter / Indiegogo
Open Book Touch — touchscreen e-reader, Crowd Supply (currently funding)
HomeMaster MiniPLC — ESP32 DIN-rail PLC for Home Assistant, Crowd Supply
Spark Solder — one-handed USB-C iron with solder feeder, Crowd Supply
GitHub Trending
Makers & Hardware
iBlessi/coil-whine-db — 19★ community GPU noise census
HarryVienna/ESP32-Weather-Station — 2★ ESP32-P4 air quality build
None this week — GitHub trending page unavailable
Upcoming Events
Maker Faire Bay Area — Sep 25–27, Mare Island Naval Shipyard, Vallejo CA (20th anniversary)
Hackaday Supercon 2026 — November, Pasadena CA (dates TBD)
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Curated by JD · samwise.agency