This week’s podcast sees Elliot joined by Jenny List, as both suffer silently in the European summer heat because the sound of a desk fan would come over on the recording.

A stand-out hack of the week comes from [Bitluni], whose GPU made from thousands of cheap microcontrollers is on a scale we’ve never seen before. It’s an amazing project in itself, but the manufacturing and power consumption issues of so many processors running at the same time make for a discussion of their own.

Otherwise, we have diecasting on the bench, an impressive achievement by any measure, a Raman spectrometer, and an open source take on something like a Kei truck. In quick hacks there’s a dicussion of soldering versus crimping for high current connectors, and neon tubes used as digital logic in an organ. The recording finishes with a discussion of 7-segment display history, and whether an engineering education teaches design for manufacture.

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Episode 377 Show Notes:

Mailbag:

• We were contacted by long-time listener [Alex], with a question about the deadline for What’s That Sound entries. The podcast is recorded on Thursday evening European time, most of the time, but Wednesday evening when Tom is onboard. If you get your entry in by Wednesday morning, wherever you are, you’re safe. Good luck!
• Then we had a couple of responses to Zoe Skyforest’s pitot tube air speed sensor piece. Reese Johnson suggested that some version of this might be found in motorcycle fuel gauges, and Jeff told us about very similar differential pressure airflow sensors being used in the climate control systems of large buildings. So we’re closer than we think to these devices.

What’s that Sound:

• Have an idea what the sound is? Enter your guess here.

Interesting Hacks of the Week:

• Gluing 8192 MCUs Together To Make A GPU
• Die Casting Comes Home
  
  • Retrotechtacular: The Tools And Dies That Made Mass Production Possible

  
  

• 2026 Frikkin Lasers Challenge: A 3D-Printed Raman Spectrometer
• A New Challenger Approaches The Open Source Vehicle
  
  • A Minimal Motoring Manifesto

  
  

• The Persistent Display We Never Got
  
  • Smectic Liquid Crystals, via ScienceDirect

  
  

• Why The NES Put Out A Wobbly Picture

Quick Hacks:

• Elliot’s Picks:
  
  • Settling The Debate On Soldered Versus Crimped High-Current Connectors
  • Microdistillery For Microchemistry
  • Time Never Moves Slowly With This Clock

  
  

• Jenny’s Picks:
  
  • This KVM Runs A P4 Instead Of A Pi.
  • The Organ That Forgot To Use Transistors
  • Old Midi Instruments Don’t Like Modern Midi. What’s To Be Done?

  
  

Can’t-Miss Articles:

• A Brief History Of The Crazy Old 7-Segment Display
  
  • Why Have Seven Segments When You Can Have 21?
  • Where We’re Calculating, We Don’t Need No Seven Segments!
  • Segmented Displays – YouTube

  
  

• When An Engineering Education Doesn’t Teach You How To Really Make Anything

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