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.

[...]

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)

[...]

PCB Radiography Kindergarten.

Below is the result of test-firing a newly-installed miniature PCB radiography system.
The victim is a standard FG TRNG Analogue Unit:
Click for full resolution (Warning: 14MB)

Detail of left op amp, with bonding whiskers visible:

The substrate, aluminum RF shield frame, SMT contacts, vias, and the two layers of the PCB are clearly distinguishable. Likewise resistors (nearly transparent) [...]

The Serpent Cipher’s Key Schedule Transform is Injective.

This article is a continuation of the previous, and concludes the series.

Let’s try this somewhat different variant of the program, which represents recurring bits of the expansion symbolically (and in a slightly more readable form) [...]

Serpent Cipher’s Key Schedule in Algebraic Form: with Reduction.

This article is a continuation of the recent mega-puzzler concerning the experiment.

This variant will reduce the equations. We will omit printing the input matrix, for brevity. And so:

;; Register bitness.
(defconstant +bitness+ 32)
 
(defun flatten (l)
[...]

Terms -8…8 of the Serpent Cipher’s Key Schedule in Algebraic Form.

This article is a byproduct of the recent mega-puzzler concerning the Serpent cipher’s key expansion procedure.

Behold:

;; Register bitness.
(defconstant +bitness+ 32)
 
(defun make-reg (reg-name bitness)
"Make algebraic representation of a register (bits in descending majority)"
(loop for i from [...]

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