AppliedCritical.com High Voltage · X-Ray · Experiments
Live Lab Notes

Experimental high voltage & X-ray in the real world.

If you have a problem, if no one else can help & if you can find us, maybe you can hire... AppliedCritical.

AppliedCritical.com is where practical electronics collides with radiation detection, X-ray hardware, and home-lab experiments that probably shouldn’t be this fun.

If you have a problem, if no one else can help, and if you can find us… maybe you can hire… AppliedCritical.

High Voltage Supplies X-Ray Tubes & Detectors PMTs & Scintillators Raspberry Pi / MCU Tooling

Featured builds & write-ups

The plan is to gradually turn AppliedCritical.com into a living lab logbook. Expect deep dives, schematics, CAD snippets, and the occasional cautionary tale.

  • Home-brew PMT bias supplies and noise-hunting in plastic boxes.
  • X-ray tube experiments, shielding, and why “that seems fine” is never enough.
  • Low-noise front-ends for photodiodes, scintillators, and gamma detectors.
  • Mechanical bits: 3D-printed fixtures, vacuum hardware, and weird brackets.
$ tail -f lab.log
[OK] HV rail at 1.40 kV
[OK] Dark current within expected range
[WARN] Who left the banana plug half-seated?
[NOTE] Add better cable management soon…

Philosophy

“Applied critical” means doing dangerous-adjacent things with respect: questioning assumptions, reading datasheets, overbuilding safety, and documenting the process so future-you knows why choices were made.

Safety & disclaimer

Nothing here is an endorsement that you should repeat any experiment. If you choose to, you’re responsible for verifying local laws, best practices, and safety standards.

  • High voltage can stop your heart or cause serious burns.
  • X-ray and gamma sources can cause long-term health damage.
  • Improper shielding, interlocks, and grounding are not optional.
TL;DR: Documentation, not instructions. If you’re not sure something is safe, assume it isn’t.

Lab log & project notes

Occasional write-ups of builds, failures, and “it finally worked” moments.

PMT bias supply prototype on bench
JAN 2025 · HIGH VOLTAGE
Building a quiet PMT bias supply

First pass at a compact, low-ripple bias supply for a surplus PMT, including lessons in layout, shielding, and noise hunting.

Read entry →

Contact

Have a question about a build, want to collaborate, or want to swap war stories about surplus test gear and weird eBay finds?

Especially interested in:

  • PMT / scintillator work
  • DIY X-ray / radiation detection
  • HV probes and measurement