Retrotechtacular: The Noisy Home Computer From 1967

[Rex Malik] didn’t need an alarm clock. That’s because he had one of two “home computer terminals” next to his bed and, as you can see in the video below, it made quite a racket. The terminal looks like an ASR33 with some modifications. In 1967, it was quite a novelty and, of course, it didn’t have any real processing power. It connected to an “invisible brain” ten miles away.

What do you do with a computer in 1967? Well, it looks like you could trade stocks. It also apparently managed his shopping list and calendar. His young son also learned some letters and numbers. We’d love to hear from the young [Mr. Malik] today to find out what kind of computer he’s using now.

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Hackaday Links: September 7, 2025

Two weeks ago, it was holographic cops. This week, it’s humanoid robot doctors. Or is it? We’re pretty sure it’s not, as MediBot, supposedly a $10,000 medical robot from Tesla, appears to be completely made up. Aside from the one story we came across, we can’t find any other references to it, which we think would make quite a splash in the media if it were legit. The article also has a notable lack of links and no quotes at all, even the kind that reporters obviously pull from press releases to make it seem like they actually interviewed someone.

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Looking in the back of the Tektronix 577

Repairing A Tektronix 577 Curve Tracer

Over on his YouTube channel our hacker [Jerry Walker] repairs a Tektronix 577 curve tracer.

A curve tracer is a piece of equipment which plots I-V (current vs voltage) curves, among other things. This old bit of Tektronix kit is rocking a CRT, which dates it. According to TekWiki the Tektronix 577 was introduced in 1972.

In this repair video [Jerry] goes to use his Tektronix 577 only to discover that it is nonfunctional. He begins his investigation by popping off the back cover and checking out the voltages across the voltage rails. His investigations suggest a short circuit. He pushes on that which means he has to remove the side panel to follow a lead into the guts of the machine.

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A photo of an RPi and a note about the first lecture.

The Latest Projects From Cornell’s ECE 4760/5730

ECE 4760/5730 is the Digital Systems Design Using Microcontrollers course at Cornell University taught by [Hunter Adams]. The list of projects for spring this year includes forty write-ups — if you haven’t got time to read the whole lot you can pick a random project between 1 and 40 with: shuf -i 1-40 -n 1 and let the cards fall where they may. Or if you’re made of time you could spend a few days watching the full playlist of 119 projects, embedded below.

We won’t pick favorites from this semester’s list of projects, but having skimmed through the forty reports we can tell you that the creativity and acumen of the students really shines through. If the name [Hunter Adams] looks familiar that might be because we’ve featured his work here on Hackaday before. Earlier this year we saw his Love Letter To Embedded Systems.

While on the subject, [Hunter] also wanted us to know that he has updated his lectures, which are here: Raspberry Pi Pico Lectures 2025. Particularly these have expanded to include a bunch of Pico W content (making Bluetooth servers, connecting to WiFi, UDP communication, etc.), and some fun lower-level stuff (the RP2040 boot sequence, how to write a bootloader), and some interesting algorithms (FFT’s, physics modeling, etc.).

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Dealing With The 1970s EPROM Chaos In 2025

It could be argued that erasable programmable ROMs (EPROMs) with their quaint UV-transparent windows are firmly obsolete today in an era of various flavors of EEPROMs. Yet many of these EPROMs are still around, and people want to program them. Unfortunately, the earliest EPROMs were made during a time when JEDEC standardization hadn’t taken root yet, leading to unique pinouts, programming voltages, and programming sequences, as [Anders Nielsen] explains in a recent video.

[Anders]’s Relatively Universal-ROM-Programmer project recently gained the ability to program even the oldest types of EPROMs, something which required modifying the hardware design to accommodate EPROMs like Ti’s TMS2716 and the similar-but-completely-different TMS2516. Although not the hardest thing to support – requiring just a diode and resistor added to the BOM along with a firmware update – it’s just one of those pre-standardization traps.

As [Anders] put it, it’s sometimes good to be unencumbered by the burden of future knowledge. Who would have willingly subjected themselves to the chaos of incompatible pinouts, voltages, etc., if they had known beforehand that in a few years EEPROMs and JEDEC standardization would make life so much easier? Maybe that’s why messing with retro hardware like this is fun, as afterwards you can go back to the future.

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Pinout of 74HC595

Using The 74HC595 Shift Register To Drive 7-Segment Displays

In a recent video our hacker [Electronic Wizard] introduces the 74HC595 shift register and explains how to use it to drive 7-segment displays.

[Electronic Wizard] explains that understanding how to apply the 74HC595 can increase the quality of your projects and also help keep the demands on the number of pins from your microcontroller to manageable levels. If you’re interested in the gory details you can find a PDF datasheet for the 74HC595 such as this one from Texas Instruments.

[Electronic Wizard] explains further that a shift register is like a small one byte memory where its data is directly available on its eight output pins, no input address required. When you pulse the clock pin (CLK) each bit in the eight bit memory shifts right one bit, making room for a new bit on the left. The bits that fall off the right hand side can daisy chain into another 74HC595 going out on pin 9 and coming in on pin 14.

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Hackaday Links: August 17, 2025

We’ve studiously avoided any mention of our latest interstellar visitor, 3I/Atlas, on these pages, mainly because of all the hoopla in the popular press about how Avi Loeb thinks it’s aliens, because of course he does. And we’re not saying it’s aliens either, mainly because we’d never be lucky enough to be alive during an actual alien invasion — life just hasn’t historically been that kind to us. So chances are overwhelming that 3I/Atlas is just a comet, but man, it’s doing its level best to look like it’s not, which means it’s time to brave the slings and arrows and wade into this subject.

The number of oddities surrounding 3I/Atlas just keeps growing, from its weird Sun-directed particle stream to its extreme speed, not to mention a trajectory through the solar system that puts it just a fraction of an astronomical unit from two of the three planets within the “Goldilocks Zone” of our star — ignore the fact that at an estimated seven billion years old, 3I/Atlas likely would have started its interstellar journey well before our solar system had even started forming. Still, it’s the trajectory that intrigues us, especially the fact that it’s coming in at a very shallow along to the ecliptic, and seems like it will cross that imaginary plane almost exactly when it makes its closest approach to the Sun on October 29, which just coincidentally happens to be at the very moment Earth is exactly on the opposite side of our star. We’ll be as far as possible from the action on that date, with the comet conveniently lost in the glare of the Sun. Yes, there’s talk of re-tasking some of our spacecraft around Mars or in the Jovian system to take a peek when 3I/Atlas passes through their neighborhoods, but those are complicated affairs that show no sign of bearing fruit in the short time left before the comet heads back out into the Deep Dark. Too bad; we’d really love an up-close and personal look at this thing.

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