Dr. Daves Diversions | Outtake: SD XMDZ DC-DC boost module temperature @DrDavesDiversions | Uploaded December 2020 | Updated October 2024, 5 minutes ago.
Some Keelog and Electroware PSUs for the Commodore 64 use the tiny "SD XMDZ" boost module to provided 12V DC from their internal 5V DC switching power supply.

My experiments show the SD XMDZ is one of the hottest parts in the PSU, with its component temperatures measuring ~140F (+60C), +70F (+21C) over ambient temperature.

This is an outtake originally prepared for this video:

Electroware C64 "2-in-1" PSU heavy-duty mod (30 watts DC)
youtube.com/watch?v=daE0QzkroB8

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$C64 Turtle Graphics: Rotational Symmetries from Repeating Decimals #shorts Fun with Turtle Graphics on the Commodore 64 c. 1984! This is a visualization is of the value 1/7 (one-seventh), a rational number with a repeating decimal that forms a nice rotationally symmetric figure when its base 10 digits are used to determine the fraction of 360 degrees rotated before drawing the next line segment. Here is what I wrote today using HESwares Turtle Graphics II (c) 1983. Because this language does not have arrays, I could not simply drop the digits of 1/7 (0.14285714285714...) into an array like they do using python in the Numberphile videos (linked below). Instead, I decided to calculate each digit on each loop iteration (DRAW). Note that C64s INT() function is actually floor() and that this language, like C64 BASIC, does not have a modulo operator, which is why the calculations are more verbose. This is in the 64s 320x200 mode (HIRES!). Currently the fraction (1/7) is hard-coded, as well as the length of the repeating run (7) and the number of iterations (100). 1 HIRES 2 SET HEADING TO 0 3 MOVE TO 80-130 4 PEN DOWN 5 CALCULATE X=0 6 LABEL DRAW 7 FORWARD 50 8 CALCULATE Y=X-(INT(X/7)*7) 9 CALCULATE A=INT((1/7)*(10^Y)) 10 CALCULATE D=36*(A-INT(A/10)*10) 11 TEST IF (D=0) 12 IF TRUE JUMP POSTROT 13 ROTATE LEFT D 14 LABEL POSTROT 15 CALCULATE X=X+1 16 TEST IF (X=100) 17 IF FALSE JUMP DRAW 18 STOP Related: Plotting Pi and Searching for Mona Lisa - Numberphile https://www.youtube.com/watch?v=tkC1HHuuk7c The specific figure I plot is shown beginning at 7m20s: https://www.youtube.com/watch?v=tkC1HHuuk7c&t=7m20s The Plotting of Beautiful Curves (Euler Spirals and Sierpiński Triangles) - Numberphile https://www.youtube.com/watch?v=kMBj2fp52tA The Turtles are Coming! by David Malmberg, pp. 26-28, Commodore Power-Play, 1982, Issue 2, V1, N02, Fall (issuu.com) https://issuu.com/astarothduke/docs/commodore_power-play_1982_issue_02_v1_n02_fall David Malmberg Interview (brasslantern.org) http://brasslantern.org/community/interviews/malmberg-b.html q(D.M.: Sort of. I wrote and published a product for the Commodore-64 and VIC-20 titled TurtleGraphics, which sold approximately 80,000 copies and was translated into French and Spanish. It was actually published by a company called HESware, which I helped found. Turtle Graphics was a LOGO-like language/product designed to teach programming skills to kids from six to sixty.) ANTIC Interview 285 - Jay Balakrishnan, HESWare (audio) https://ataripodcast.libsyn.com/antic-interview-285-jay-balakrishnan-hesware$

Outtake: SD XMDZ DC-DC boost module temperature @DrDavesDiversions