The Amp Hour Electronics Podcast

Contextual Electronics is “still a thing”. Sydney hosted the International Astronautical Congress (IAC). The IAC is the “big space event of the year,” held annually in a different city. Chris noted that US space funding seems low, leading some friends to move from NASA to private industry. Dave recorded two walkaround videos: a 30-minute bird’s eye view using a GoPro on a pole and a physical hour-long walkaround. Large companies had private stands, while smaller, two-man companies had sub-booths within their country’s larger rented stand (e.g., South Africa, Germany, Poland). Niche companies included those selling “space connectors,” described as regular connectors sold at potentially 10 times the price to space customers. Australia had a large presence, with stands for the country and individual states (Victoria, New South Wales, Tasmania) hosting local niche space gear firms. Dave toured a new, completely mobile Mission Control facility built into a semi-trailer van. This unit is designed as a generic platform with screens, server racks, and redundant power, allowing any space company to install their own servers and operate anywhere in Australia. An Australian company specialized in “Space lube” (lubricants for satellites and actuators), necessary because water-based lubricants would boil off or freeze up and cause gear to seize. Chris has a new “quasi obsession” with the old technology of DIN rail. He is using 3D printers to mount development boards onto DIN rail to organize his desk. DIN rail is common in Australia and Europe for electrical switchboards and automation equipment (PLCs, power supplies). Dave sent a photo of “Fish Pointer’s” organized desk, which Chris identified as using “Gridfinity,” an ad hoc, modular standard popular in the 3D printing community, often associated with Zack Friedman of Voidstar Labs. Dave runs a Creality K1 3D printer that is networked, allowing him to control and print remotely. Chris purchased a filament dryer for only $42 to combat the issue of filament going brittle due to moisture. Dave recounted his attempt to sort 330 tins of salvaged parts (feet, spacers, grommets) from vintage test gear. The space industry is currently “so hot” due to private funding, unlike the “dead” industry 10 to 15 years ago. It is now easy to book a payload slot on a launch vehicle like SpaceX. Dave said that Firefly was actually “begging” people to put payloads on its Moonlander to help fund the mission, though that’s source unknown. It was supported by CPLS as part of NASA. The Commodore Corporation recently changed hands, and a consortium of enthusiasts released a new Commodore 64 Ultimate, featuring a transparent keyboard PCB signed by original designers, including Jerry Ellsworth. The appeal is nostalgia, as modern chips far outperform the 6510 CPU it uses. Chris bought a split, ergonomic Corne V4 keyboard (RP2040 chip) from AliExpress for $68. The key feature is working with Vial, a pleasant web serial-based app for reconfiguring key mappings. Dave stated he hates split keyboards and rechargeable keyboards that only last a week. Dave is installing 75 kWh of beefy outdoor battery packs (800-900 kg total) received “free” due to a government subsidy. He poured a new, completely reinforced concrete slab rated for over 1,500 kg to support the batteries on a flat surface, using pre-welded mesh instead of tying rebar. The new system includes an 8 kW inverter. Dave intends to install a changeover switch to run the house off the batteries if the power grid fails. Dave noted he mainly wants the “warm fuzzy” feeling of running his entire house on solar and batteries.

Welcome Jerry Twomey (Effective Electrons) author of the book, Applied Embedded Electronics: Design Essentials for Robust Systems. Chris first heard Jerry on Embedded.fm last year. Jerry’s Background and Book Motivation: Jerry shares his quick history, moving from the Boston area to San Jose (Silicon Valley) and eventually to San Diego, where he has worked across diverse sectors including consumer electronics, aerospace, defense projects, DARPA research, and medical electronics. His book focuses on how to develop robust systems, providing guidance that is timeless rather than applications manuals that quickly become outdated. The Analog Problem: Although modern systems may be digital end-to-end, Jerry emphasizes that the predominant causes of failure and design difficulties are often analog in nature. Academic study often teaches ideal signals but neglects real-world issues like inductance, noise, and cross-coupling. Consulting Experience & Troubleshooting: Jerry discusses being called in to fix systems that failed strenuous regulatory testing for medical devices, where reliability is first and foremost (similar to an aerospace way of thinking). Failures often stemmed from basic issues like a lack of ESD protection, absence of error correction in data streams, insufficient detection of errors, and common mode noise rejection problems. High-Speed Data and Signal Integrity: At high data rates, communication becomes a “communications channel problem,” not truly a digital one. When bits are underneath a tenth of a nanosecond, the communication turns into multiple standing wave transitions. The two primary limits on performance are rise and fall times and distance traveled. Real-World Applications: Jerry has worked extensively on medical devices, including early-generation Dexcom glucose monitoring systems (two on-body monitors and a hospital insulin pump/monitor), and a wearable EEG monitor. He also worked on a system that required packing five video cameras into an endoscope distal head, measuring 11 mm in diameter and 13 mm long. Architecting Systems and Identifying Bottlenecks: When starting a new project, Jerry suggests defining needs and interfaces and looking at the system as a black box. Engineering time should focus on the bottleneck—the hardest part of the system. For medical implantables, this might be minimizing power consumption down to virtually nothing, which could take up 90% of the effort. Power System Design: Jerry advises purchasing commercial AC-to-DC converters due to competitive pricing. He notes that switching supplies (buck converters) commonly introduce noise that can lead to EMI failures or corrupt sensitive analog front ends. A classic case of “digital thinking in an analog scenario” is when a sensitive analog front end is powered by a noisy switching converter. Working with Embedded Teams: Jerry prefers guiding embedded teams toward “self-discovery,” using bench time and empirical measurement (such as comparing grounds on a scope) to demonstrate non-ideal connections and grounding issues. He advises against the “seagull manager” approach. Grounding Best Practices: For integrated circuits (chips), designs must be fully differential because securing a good hard ground reference is impossible. On singular circuit boards, a common uncut ground plane (dedicated ground plane, often multiple layers stitched together with vias) is the recommended approach. Cutting the ground plane is discouraged as it can create a slot antenna, increasing the signal radiating from the board by about 7 dB. Jerry has published rules on grounding. Engineering Intuition vs. LLMs: Jerry notes that intuition is gathered through painful learning experiences and guidance from experienced designers. He expresses concern over the reliance on LLMs (Language Learning Models), which, while improving, can confidently provide incorrect answers, especially regarding complex topics like signal grounding. Limits to Moore’s Law: CMOS scaling is approaching physical limits, likely unable to go below 10 or 11 nanometers. Modern performance gains are achieved through more parallel processing, not significantly faster clock rates, which have plateaued around 5 GHz due to parasitics and timing limitations. Jerry’s article discusses this topic. RISC Architectures: The industry benefits from migrating to RISC (Reduced Instruction Set Computing) architectures (like ARM) because they eliminate useless architecture and transistors associated with complex instruction sets (like x86). Find Jerry on Effective Electrons and on LinkedIn

Welcome back Tim Ansell! Tim’s past appearances and previous work Discussing Tomu on 375 Discussing Fomu on 456.3 Discussing the open source PDK on 501 Tim’s previous work at Google involved releasing a manufacturable open-source PDK (Process Development Kit), which contains the fundamental information needed to create integrated circuits. Key open-source tools discussed include OpenROAD (a backend compiler for IC design) and Open Lane (an end-to-end suite turning chip descriptions (RTL) into manufacturing data (GDS)). Andreas had been on the show talking about his work on OpenROAD. Not discussed on the show but after Efabless went away, Open Lane has been replaced with LibreLane. Efabless, a VC-backed startup, shut down in early 2025 due to investor disagreements. Efabless previously provided pooled manufacturing access (similar to OSH Park for PCBs) using the SKY130 process from Skywater in Minnesota. A Skywater run costs $200k–$300k, which Efabless divided by 40 to reach roughly a $10k price point per slot. Tiny Tapeout Matt Venn’s Tiny Tapeout program further subdivides the manufacturing costs, making it the cheapest way to create custom silicon, typically costing around $300 per design. Tiny Tapeout lowers the barrier to entry, allowing people to “just try it and see if you like it,” similar to writing a “hello world” program. The program has already processed almost 3,000 projects, demonstrating high community demand when costs are low. Despite limitations, advanced projects are possible: a developer taped out a Linux capable SOC using open-source tools and the Tiny Tapeout space. Introducing Wafer Space Tim started Wafer Space, based in Singapore, to provide community access to open-source manufacturing after Efabless ceased operations. Wafer Space focuses on the GF180MCU PDK (Global Foundries 180 nm process), which is a much cheaper technology manufactured in Singapore. The core offering is a low-volume production run: $7,000 USD gets you 1,000 chips back. This volume is enough for prototyping and shipping a small product (e.g., 500 units). The design envelope area is 3.8 x 5 mm (20 mm squared) using the 180 nm process. Interested parties should sign up via the Crowd Supply page.  The deadline for purchase is the November 28th and submissions are due by December 3rd, with delivery by March 15th. Manufacturing & Packaging By default, customers receive bare silicon die Tim is working with PCB manufacturers (like JLC PCB, PCB Way, Seed Studio) to offer Chip on Board (COB) wire bonding assembly onto custom PCBs (think black epoxy blob on a PCB) COB packaging is significantly cheaper (sub-$2) than standard packaging houses (which often charge around $7 per chip). This approach also provides faster iteration speed, as PCB manufacturers offer quick turnaround times (sometimes 3 days) compared to typical packaging houses (3 months) Getting Started & Resources If you are new to chip design, starting with Tiny Tapeout’s click and drag tools is highly recommended. Matt Venn previously talked/sang about Siliwiz More advanced tools include Verilog and VHDL (coding style) or KLayout and Magic (drawing shapes, similar to PCB design). To follow the project or seek help, join the Wafer Space Discord New services offering open-source silicon manufacturing include IHP (Europe/130 nm) and Chip Foundry (US/Skywater), increasing ecosystem resiliency. Website: Wafer.space Sign up on the CrowdSupply campaign

Dave bought a lemon laptop Chris officially has solar that is installed, working, and is effectively an appliance at this point… Duke Energy and North Carolina nuclear mix The impact of batteries on the grid The Duck Curve is something Chris and Ari discussed on ep650 Open circuit voltage on panels Dave did a repair on a tennis ball machine Chris designed a board with test points too small Accupuncture jbc High cost vs low cost rework tweezers Nanofix YouTube Channel Tested Ugly multimeter review

Todd Bailey, an engineer at Muon Space with a rich background in electric propulsion, shares insights into the evolution of rocket technology. He discusses the challenges and triumphs of transitioning from major corporations to startups in the aerospace industry. The conversation delves into innovative uses of zinc as a propellant in Hall effect thrusters, and the importance of mentorship and resilience in navigating high-stakes decisions. Bailey also reflects on the influence of science fiction on real-world technological ambitions, particularly the legacy of Zefram Cochrane's warp drive.

Dave is starting a new project for a lab timer called the uTimer Timelapse Geerling videos about clocks Mitxela clock Transflective displays Dave is looking at LCDs like this one Dropping Rs vs Ls Font chip .5mm pin pitch on the connectors Chris is making a new breakout board that is effectively a sensors shield for a Bluetooth chip. It’s the first time he’s using the service and it was a pleasant completely hands-off experience. Mike Harrison USB C barrel jack JLC DFM plugin for KiCad Python script to pull EasyEDA parts into KiCad Chris is designing around this $3 board with an nRF52840A de minimus tariff exemptions are gone in the us North Korea is putting forward software engineering candidates that are actually teams of workers Mini PC production at BeeLink Stephen Hawes on The Amp Hour Stephen documented the process of getting the Opulo v4 through certification Chris has solar install issues Dave is dealing with removing downpipes Dave is getting battery extension 50 kWh

Andrew Seddon, the Founder and CEO of CircuitHub, revisits the podcast after 12 years to discuss the evolution of electronics manufacturing. They cover the necessity of adapting to diverse component selections and the challenges of maintaining efficient SKU stockpiles. Seddon humorously compares component distributors to grocery stores while exploring innovative practices like AI integration and quick-turn PCB design. He also highlights the impact of rising tariffs on manufacturing choices, particularly in the U.S., which is pushing companies to explore lower-cost areas.

Matt Brown, a security researcher at Brown Fine Security and YouTuber, dives into the intriguing world of IoT and hardware security. He shares his experiences reverse engineering a smart smoker controller and discusses the critical need for secure design in consumer devices. Key topics include managing private keys, vulnerabilities of Linux-based devices, and the importance of threat modeling. Matt also explores advanced security techniques, essential tools for reverse engineering, and his upcoming IoT security newsletter, all while emphasizing the evolving challenges in connected technology.

Welcome Tim from Mitxela! Introduced by Mike Harrison, past guest of the show Fluid pendant Volumetric display London hackspace https://matthias-research.github.io/pages/tenMinutePhysics/index.html FLIP in Blender CHNT36ta Pick and place doing 0201 Precision Clock Sewing machine (check out that GIF!) Secret life of machines – Tim Hunkin Isaac Singer Tim has many Lathe projects on the hardware projects page Flag Steam Engine Learn how to machine from MrPete222’s YouTube channel Schlock Mercenary (Comic) Sprite tm on The Amp Hour Gameboy advance link cable Writing a gameboy emulator  Emulators got him into electronics No$ (“nocash”) emulator AVR instruction set MIDI CNLohr on The Amp Hour https://mitxela.com/projects/slide2 Forcing brainfuck (language) quop movfuscator Puzzles Spacechem (Game) Zach Barth of Zachtronics on The Amp Hour  babaisu LED errings watchdog timer allows ridiculously low power 1 way loader  autobauding Find all of Tim’s projects on mitxela.com Watch the latest videos on the mitxela youtube

Dave found a wrist mounted DMM that looks…inadvisable We’ll discuss the survey results next time! Florin Cocos of VoltLog Great Scott Sam Aldaher on the show last week Gerald Undone did a studio tour with Captain Disillusionment Short videos Dave using a go-pro on a bike Separate gyro file to stabilize D-y hybrid inverter Chart Remote shell Cline Chris is finally getting solar open energy monitor Emporia vue Sense We talked with Joe Bamberg when he worked there Driving back from canberra Ben Krasnow makin’ magnets! Bluetooth videos