Teardown

466 Articles

Retro Calculator Panders To Trekkies… Or Trekkers

July 19, 2024 by 9 Comments

Back in 1976, when calculators were not common or cheap, a company named MEGO made the Star Trekulator: a calculator sporting a Star Trek theme. However, it was a bit odd since the calculator didn’t correspond to anything you ever saw on the TV show. It was essentially a very simple calculator with a Star Trek picture and some blinking LEDs. [Computer History Archives Project] has two examples of the rare calculator and shows them off, including the insides, in the video below. We’ve also included a vintage commercial for the device a little farther down.

Inside the 5-inch by 9.5-inch cabinet was an unremarkable printed circuit board. The main component was a TI calculator chip, but there were a surprising amount of other components, including three that [Computer History Archives Project] could not identify.

MEGO was known for making Star Trek toys, including a cassette player that (sorta) looked like a tricorder and communicator walkie-talkies. We wish they’d made the calculator look like some sort of prop from the show, although the beeping noises, we suppose, were supposed to sound like the Star Trek computers.

Honestly, we want to 3D print a case to replicate this with modern insides that can drive a display to put different Trek clips and sound effects out. Now, that would be something. Maybe [Michael Gardi] can take a look at it when he’s got a spare minute. If anything, the calculator looks too advanced to be on the original series. They should have gone VFD. Although Mr. Spock has been seen with a flight slide rule (an E6-B, if we recall). We prefer our props to look like the real ones, thank you.

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Unlocking The Mystery Of An Aircraft ADI

July 8, 2024 by 13 Comments

If you’ve ever seen the cockpit of an airplane, you’ve probably noticed the round ball that shows your attitude, and if you are like us, you’ve wondered exactly how the Attitude Direction Indicator (ADI) works. Well, [msylvain59] is tearing one apart in the video below, so you can satisfy your curiosity in less than 30 minutes.

Like most things on an airplane, it is built solidly and compactly. With the lid open, it reminded us of a tiny CRT oscilloscope, except the CRT is really the ball display. It also has gears, which is something we don’t expect to see in a scope.

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Korean Multifunction Counter Teardown

July 7, 2024 by 5 Comments

[Thomas Scherrer] likes to tear down old test equipment, and often, we remember the devices he opens up or — at least — we’ve heard of them. However, this time, he’s got a Hung Chang HC-F100 multifunction counter, which is a vintage 1986 instrument that can reach 100 MHz.

Inside, the product is clearly a child of its time period. There’s a transformer for the linear supply, through-hole components, and an Intersil frequency counter on a chip. Everything is easy to get to and large enough to see.

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A Vintage AC Bridge Teardown

June 30, 2024 by 2 Comments

If you ever encounter a British engineer of a certain age, the chances are that even if they use a modern DMM they’ll have a big boxy multimeter in their possession. This is the famous Avo 8, in its day the analogue multimeter to have. Of course it wasn’t the only AVO product, and [Thomas Scherrer OZ2CPU] is here with another black box sporting an AVO logo. This one’s an AC bridge, one of a series of models manufactured from the 1930s through to the late 1940s, and he treats us to a teardown and restoration of it.

Most readers will probably be familiar with the operation of a DC Wheatstone Bridge in which two resistances can be compared, and an AC bridge is the same idea but using an AC source. A component under test is attached to one set of terminals while one with a known value is put on the other, and the device can then be adjusted for a minimum reading on its meter to achieve a state of balance. The amount by which it is adjusted can then be used as a measure of the difference between the two parts, and thus the value of an unknown part can be deduced.

In the case of this AVO the AC is the 50Hz (remembering that this is a British instrument) mains frequency, and the reading from the bridge is taken via a single tube amplifier to a rectifier circuit and the meter. Inside it’s a treasure trove of vintage parts with an electrolytic capacitor that looks as though it might not be original, with a selenium rectifier and a copper oxide signal diode in particular catching our eye. This last part is responsible for some reading anomalies, but after cleaning and lubricating all the switches and bringing up the voltage gently, he’s rewarded with a working bridge. You can see the whole story in the video below the break.

Test equipment from this era is huge, so perhaps not all of you have the space for something like this. Some of us have been known to own other AVO products though.

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$3 Smartwatch Can Run Python

June 26, 2024 by 8 Comments

[Poking Technology] doesn’t think much of his new smartwatch. It is, by his admission, the cheapest possible smartwatch, coming in at about $3. It has very few useful features but he has figured out how to port MicroPython to it, so for a wrist-mounted development board with BLE, it might be useful. You can check it out in the video below.

The first step is a teardown, which reveals surprisingly little on the inside. There’s a tiny battery, a few connections, a display, and a tiny CPU board. There are, luckily, a few test pads that let you get into the CPU. What do you get? A 24 MHz Telink CPU with 512k of flash and 16k of RAM, along with all the other hardware.

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All About CRTs

June 25, 2024 by 76 Comments

For old-timers, CRTs — cathode ray tubes — were fixtures as kids sat in front of TVs watching everything from Howdy Doody to Star Trek. But there’s at least one generation that thinks TVs and computer monitors are flat. If that describes you, you might enjoy [The 8-Bit Guy’s] coverage of how CRTs work in the video below.

CRTs were heavy, took high voltage, and had a dangerous vacuum inside, so we really don’t miss them. The phosphor on the screen had a tendency to “burn in” if you showed the same image over and over. We don’t miss that either.

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Digital Meter From 1973, A Teardown

May 28, 2024 by 8 Comments

[Thomas] found an interesting probable millivoltmeter with some Beckman displays. Like many instruments from that time period, this one had a lot of tobacco smoke residue inside. The display unit inside had a sticker that not only showed the company that made it, but also had their Telex number on it, another sign of the times. You can see the device in the video below.

The unit looked like a one-off made by a hobbyist or a technician but the case looked suspiciously like old Bang and Olfusen equipment. Someone in the video comments mentions it was built for the service department.

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