“Finite Field Arithmetic.” Chapter 18C: Peh School: Generation of Cryptographic Primes.

This article is part of a series of hands-on tutorials introducing FFA, or the Finite Field Arithmetic library. FFA differs from the typical “Open Sores” abomination, in that — rather than trusting the author blindly with their lives — prospective users are expected to read and fully understand every single line. In exactly the same [...]

“Finite Field Arithmetic.” Chapter 18B: "Cutouts" in Peh.

This article is part of a series of hands-on tutorials introducing FFA, or the Finite Field Arithmetic library. FFA differs from the typical “Open Sores” abomination, in that — rather than trusting the author blindly with their lives — prospective users are expected to read and fully understand every single line. In exactly the same [...]

“Finite Field Arithmetic.” Chapter 18A: Subroutines in Peh.

This article is part of a series of hands-on tutorials introducing FFA, or the Finite Field Arithmetic library. FFA differs from the typical “Open Sores” abomination, in that — rather than trusting the author blindly with their lives — prospective users are expected to read and fully understand every single line. In exactly the same [...]

“Finite Field Arithmetic.” Chapter 17: Introduction to Peh.

This article is part of a series of hands-on tutorials introducing FFA, or the Finite Field Arithmetic library. FFA differs from the typical “Open Sores” abomination, in that — rather than trusting the author blindly with their lives — prospective users are expected to read and fully understand every single line. In exactly the same [...]

X-Ray Large-Format Kindergarten.

Below is the output of a new test-fire of the PCB radiography system, this time using FujiFilm “Super HR-T Medium Speed” (25×20 cm) film in place of the earlier self-developing dental Eco-30.

However, the time has not yet come to molest the MacIvory — first, we must characterize the film and the [...]

X-Ray Microscopy of Symbolics "Ivory" CPUs.

I currently have three Symbolics MacIvory CPUs. (Do you, reader, have one to sell? Please leave a comment!)

One is currently installed in a working machine and was not yet molested; the two remaining chips, I obtained in 2017 by bartering away a Symbolics 3620.

At some point I will cut one or more of the “Ivories” [...]

X-Ray Spectrography Kindergarten.

This article is a continuation of “X-Ray Microscopy Kindergarten.”.

Preliminary experiment with multi-energy x-ray (colour channel combination), distinguishing materials by absorption at different wavelengths.

The tube appears to exhibit some “heel effect” at the longer wavelengths.

Exposure: 75 sec. @ 35kV, 21kV, 20kV (R, G, B) [...]

X-Ray Stereography Kindergarten.

This article is a continuation of “X-Ray Microscopy Kindergarten.”.

Here, we see a stereo pair (approx. +/- 25 deg. one-axis rotation of the object from the horizontal plane, while film is stationary) of the device from before.

The vias are clearly distinguishable.

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X-Ray Microscopy Kindergarten.

This article is a continuation of “PCB Radiography Kindergarten, Continued.”.

The radiography system is equipped with a “microfocus” tube, and its beam has a 30 degree spread cone. So we can get a look at that very same FG TRNG XC9572 CPLD seen earlier, but with 2x magnification:

Click for full resolution (Warning: [...]

PCB Radiography Kindergarten, Continued.

This article is a continuation of “PCB Radiography Kindergarten”.

This was a second test-fire of that radiography system, using yet-another board where I already know where everything is (on account of having designed it.)

This time, the victim is a FG TRNG Mainboard:

Click for full resolution (Warning: 16MB)

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