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I built a 10 inch mini rack from aluminium extrusions
a month ago
- The author built a DIY 10-inch mini rack using 20mm aluminum extrusions to tidy up six 1L PCs and external power bricks.
- Instead of 3D-printed or prebuilt metal shelves, custom-cut aluminum sheets were used, though alignment was tricky.
- Two 10-inch rack-mount PDUs had to be mounted vertically due to extrusion interference, and external power bricks caused clutter.
- Cooling involved USB-to-fan-header adapters, and networking included separate gigabit and 2.5Gbit switches for VM migrations.
- Total cost was about €313, excluding fans, with side panels in aluminum and top/bottom in wood, improving desk organization.
Homemade Transistor from Cadmium Sulfide Photocell (2009)
25 days ago
- A homemade FET was successfully created using a cadmium sulfide photocell with an insulated gate improvised from scotch tape and water.
- The experiment required darkness to avoid light saturation, and slight light could improve performance; the device showed transistor action with power gain but low voltage gain.
- Gate voltage swings of 75-175 VDC (reversible polarity) controlled photocell current, with high gate impedance leading to high power gain despite minimal gate current.
- The device acted as an enhancement-depletion FET: positive gate voltage increased current, negative decreased it, with dynamic response and inverted sawtooth waveform output.
- A functional amplifier circuit using the homemade transistor amplified 60 Hz body buzz, demonstrating practical power gain, though voltage gain was low (~1/10).
How to build a circular LCD clock
12 days ago
- Built a wall clock using Waveshare's 7-inch circular LCD screen connected to a Raspberry Pi.
- Required hardware includes a Raspberry Pi (3B+ or higher recommended), microSD card, USB-C power supply, and cables for connectivity.
- Used Raspberry Pi OS and VNC for remote control, with touch gestures enabled for navigation.
- Brightness can be adjusted via hardware buttons or software scripts depending on Raspberry Pi model.
- Created custom clock faces displayed through a browser in fullscreen mode, with examples like Swiss railway clock and minimalist designs.
Panel meter calculator with floating point
12 days ago
- A panel meter calculator with floating point display was created, featuring six SO-45 panel voltmeters and one vintage edgewise meter for the display.
- The project involved making a custom acrylic panel with CNC-milled openings and spray-painted details for a three-dimensional look.
- The enclosure was crafted from thin maple lumber with a custom keypad layout, using NKK JF series tactile switches and vinyl decals for keys.
- An 8-bit AVR128DA28 MCU controls the calculator, using PWM to drive the meters and a 4x4 grid for keypad scanning, with fixed-point arithmetic to avoid accuracy issues.
- The calculator's UI handles fractions, negative numbers, and errors, with specific key functions like repeated operations and a dual-press '=' for clearing state.
Stenchill: 3D Printable Solder Paste Stencil Generator
7 days ago
- StenchillBeta provides a free service to generate 3D-printable PCB stencil files from uploaded Gerber files.
- 3D-printed stencils are suitable for prototyping and small batches, especially for components 0603 and larger.
- The platform offers features like a KiCad plugin, a step-by-step guide for beginners, and user community previews.
- Recommended 3D printing settings include PLA or PETG material, 0.2mm nozzle, 0.1mm layer height, and 100% infill for optimal results.
- Stencil use simplifies solder paste application, speeding up PCB assembly compared to manual syringe methods.
I learned PCB design, 3D printing and C just to listen to music
a day ago
- Built a music streamer with a 17-inch LP-sized display to show album artwork, motivated by nostalgia for physical cover art.
- Hardware includes a 17" industrial IPS LCD (1920x1920), Radxa CM3 compute module, custom carrier board, USB-C PD power, USB-C for DAC, Gigabit Ethernet, and 12V trigger.
- Designed a thin enclosure in FreeCAD, learned parametric CAD and 3D printing, iterated through four board revisions to achieve working hardware.
- Software uses shairport-sync for AirPlay on a minimal Alpine Linux, with GPU-accelerated display app that cross-fades 4MP images at 60 fps.
- Added an out-of-band protocol extension to stream full-resolution artwork (AirPlay only sends low-res ~500x500 pixels).
- Device always on, consumes <2W when idle, wakes automatically on streaming, powers amplifier via 12V trigger; total ~24W at full brightness.
- Considering a Kickstarter campaign; sign-up link provided for updates.

Hasty Briefsbeta

#diy electronics

I built a 10 inch mini rack from aluminium extrusions

Homemade Transistor from Cadmium Sulfide Photocell (2009)

How to build a circular LCD clock

Panel meter calculator with floating point

Stenchill: 3D Printable Solder Paste Stencil Generator

I learned PCB design, 3D printing and C just to listen to music