This Expedient Microfiche Reader Illuminates Retro Datasheets

December 20, 2020 by Dan Maloney 22 Comments

You have to be of a certain vintage to remember doing research on microfilm and microfiche. Before the age of mass digitization of public records, periodicals, and other obscure bits of history, dead-tree records were optically condensed onto fine-grain film, either in roll form or as flat sheets, which were later enlarged and displayed on a specialized reader. This greatly reduced the storage space needed for documents, but it ended up being a technological dead-end once the computer age rolled around.

This was the problem [CuriousMarc] recently bumped into — a treasure trove of Hewlett-Packard component information on microfiche, but no reader for the diminutive datasheets. So naturally, he built his own microfiche reader. In a stroke of good luck, he had been gifted a low-cost digital microscope that seemed perfect for the job. The scope, with an HD camera and 5″ LCD screen, was geared more toward reflective than transmissive use, though, so [Marc] had trouble getting a decent picture of the microfiches, even with a white paper backing.

Version 2.0 used a cast-off backlight, harvested from a defunct DVD player screen, as a sort of light box for the stage of the microscope. It was just about the perfect size for the microfiches, and the microscope was able to blow up the tiny characters as well as any dedicated microfiche reader could, at a fraction of the price. Check out the video below for details on the build, as well as what [Marc] learned from the data sheets about his jackpot of HP parts.

With the wealth of data stored on microforms, we’re surprised that we haven’t seen any readers like this before. We have talked about microscopic wartime mail, though.

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Low-Tech Fix Saves Expensive, High-Tech TV From Junk Pile

October 27, 2020 by Donald Papp 67 Comments

Wiggling this connector caused the backlight to turn off and on.

[Tweepy]’s TV stopped working, and the experience is a brief reminder that if a modern appliance fails, it is worth taking a look inside because the failure might be something simple. In this case, the dead TV was actually a dead LED backlight, and the fix was so embarrassingly simple that [Tweepy] is tempted to chalk it up to negligently poor DFM (design for manufacture) at best, or even some kind of effort at planned obsolescence at worst.

What happened is this: the TV appeared to stop working, but one could still make out screen content while shining a bright light on the screen. Seeing this, [Tweepy] deduced that the backlight had failed, and opened up the device to see if it could be repaired. However, the reason for the backlight failure was a surprise. It was not the power supply, nor even any of the LEDs themselves; the whole backlight wouldn’t turn on because of a cheap little PCB-to-PCB connector, and the two small spring contacts inside that had failed.

The failed connector, once cut open, showed contacts in poor condition (click to enlarge). It was ditched for a soldered connection, and the TV lived again.

From the outside things looked okay, but wiggling the connector made the backlight turn on and off, so the connection was clearly bad. Investigating further, [Tweepy] saw that the contact points of the PCBs and the two little conductors inside the connector showed clear signs of arcing and oxidation, leading to a poor connection that eventually failed, resulting in a useless TV. The fix wasn’t to clean the contacts; the correct fix was to replace the connector with a soldered connection.

Using that cheap little connector doubtlessly saved some assembly time at the factory, but it also led to failure within a fairly short amount of time. Had [Tweepy] not been handy with a screwdriver (or not bothered to investigate) the otherwise working TV would doubtlessly have ended up in a landfill.

It serves as a good reminder to make some time to investigate failures of appliances, even if one’s repair skills are limited, because the problem might be a simple one. Planned obsolescence is a tempting doorstep upon which to dump failures like this, but a good case can be made that planned obsolescence isn’t really a thing, even if manufacturers compromising products in one way or another certainly is.

An RGB Backlight For The Nokia 5110 LCD

July 4, 2020 by Tom Nardi 13 Comments

Hardware hackers love the Nokia 5110 LCD. Or at least, they love the clones of it. You can pick up one of these panels for a couple bucks wherever electronic bits and bobs are sold, and integrating it into your project is a snap thanks to all the code and documentation floating around out there. But while it might be cheap and reliable, it’s not a terribly exciting component.

Which is perhaps why [Miguel Reis] thought he’d spruce it up a bit with an RGB backlight. While we’ll admit that this hack is mostly about looking cool, it’s not entirely without practical application. If your gadget experiences some kind of fault, having it flash the LCD bright red is sure to get somebody’s attention from across the room.

The board itself is very straightforward, with four MHPA1010RGBDT RGB LEDs and a couple of passives to keep them happy. The Nokia 5110 LCD module just pops right on, and beyond the extra pins added for the three LED colors, gets wired up the same as before. The backlight LEDs just need a few spare GPIO pins on your microcontroller to drive them, and away you go.

[Miguel] is currently selling his RGB version of this iconic LCD on Tindie for only a couple dollars more than the standard version, so it looks like a pretty cheap way to add a little bling to your next project. (Tindie is owned by Supplyframe, which also owns Hackaday. But they didn’t put us up to adding this link.)

New Depths For IMac Repair

March 3, 2020 by Bryan Cockfield 17 Comments

There’s not much economic sense in fixing a decade-old desktop computer, especially when it’s the fancy type with the screen integrated into the body of the computer, and the screen is the thing that’s broken. Luckily for [JnsBn] aka [BEAN] the computer in question was still functional with a second monitor, so he decided to implement a cheap repair to get the screen working again by making it see-through.

The only part of the screen that was broken was the backlight, which is separate from the display unit itself. In order to view at least something on the screen without an expensive replacement part, he decided to remove the backlight altogether but leave the display unit installed. With a strip of LEDs around the edge, the screen was visible again in addition to the inner depths of the computer. After a coat of white Plasti Dip on the inside of the computer, it made for an interesting effect and made the computer’s display useful again.

While none of us, including the creator, recommend coating the inside of an iMac with Plasti Dip due to the risk of fire and/or other catastrophic failure, there’s not much to lose otherwise. Just don’t shove this one into the wall. Continue reading “New Depths For IMac Repair” →

Great Artificial Daylight Via Broken TVs

August 17, 2019 by Lewin Day 34 Comments

[DIY Perks] has long been a fan of lights that accurately mimic real daylight. Often choosing high-quality LEDs for his projects, lately he’s taken a different tack – using broken televisions to produce attractive home lighting solutions.

The hack involves removing the backlight from the damaged television or monitor. These have a powerful white light inside, but the real key is that they also features a Fresnel lens. This helps the backlight appear very similar to a real skylight, due to the way it scatters light around the room.

Due to the difficulty of driving most LED and CCFL backlights, the project strips the original lighting out and replaces it with a set of high-CRI LED strips readily available off eBay. These are easily driven from 12 volts and give a white light more similar to actual daylight compared to most backlights. With the LEDs in place, the monitor’s original diffusers and Fresnel lens are put back in place, and the light is finished off with an aluminium frame.

Fitted to an angled ceiling, the light really does look as if actual sunlight is streaming through a window on a rainy day. It’s a pleasant effect that does a great job of lighting a room, and we suspect it would be excellent for general video work, too. [DIY Perks] is no stranger to a good studio light build, after all. Video after the break.

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Vintage Audio Gear Gets A Display Upgrade

January 13, 2019 by Dan Maloney 4 Comments

The lengths the retrocomputing devotee must go to in order to breathe new life into old gear can border on the heroic. Tracing down long-discontinued parts, buying multiple copies of the same unit to act as organ donors for the one good machine, and when all else fails, improvising with current productions parts to get that vintage look and feel.

This LCD display backlighting fix for a vintage audio sampler falls into that last category, which was pulled off by [Inkoo Vintage Computer]. The unit in question is an Akai S1100 sampler, a classic from the late 1980s that had already been modified to replace the original floppy drive with a USB reader when the backlight on the LCD began to give out. Replacements for the original electroluminescent backlight are available, but [Inkoo] opted for a cheaper way out. An iPhone 6s 6 Plus backlight was an inexpensive option, if it could be made to fit. Luckily, [Inkoo] was able to trim the diffuser without causing any electrical issues. A boost converter was needed to run the backlight from the sampler’s 5 V DC rail, and interfacing the backlight’s flexible circuitry to the 80s-era copper wiring was a bit fussy, but the results were great. The sampler’s LCD is legible again, and looks just like it might have in the studio back when [Depeche Mode] and [Duran Duran] were using it to crank out hits.

As much as we like this repair, it doesn’t imply that EL is a dead technology. Far from it – [Ben Krasnow] is using it to create unique displays, and EL wire makes for some dazzling wearables. It doesn’t last forever, but while it does, it’s pretty neat stuff.

Trashed TV Gets RGB LED Backlight

October 11, 2018 by Tom Nardi 34 Comments

It might not be obvious unless you’ve taken one apart, but most of the TVs and monitors listed as “LED” are simply LCD panels that use a bank of LEDs to illuminate them from behind. Similarly, what are generally referred to as “LCDs” are LCD panels that use fluorescent tubes for illumination. To get a true LED display with no separate backlight, you need OLED. Confused? Welcome to the world of consumer technology.

With those distinctions in mind, the hack that [Zenodilodon] recently performed on a broken “LED TV” is really rather brilliant. By removing the dead white LED backlights and replacing them with RGB LED strips, he not only got the TV working again, but also imbued it with color changing abilities. Perfect for displaying music visualizations, or kicking your next film night into high gear with a really trippy showing of Seven Samurai.

In the video after the break, [Zenodilodon] starts his RGB transplant by stripping the TV down to its principal parts. The original LEDs were toasted, so they might as well go straight in the bin alongside their driver electronics. But the LCD panel itself was working fine (tested by shining a laser pointer through it to see if there was an image), and the plastic sheets which diffuse the LED backlight were easily salvaged.

With the old LEDs removed, [Zenodilodon] laid out his new strips and soldered them up to the external controller. He was careful to use all white wires, as he was worried colored wires might reflect the white light and be noticeable on the display. After buttoning the TV back up, he went through a few demonstrations to show how the image looked with the white LEDs on, as well as some interesting effects that could be seen when the LEDs are cycling through colors.

The RGB strips don’t light up the display as well as the original backlight did, as there are some obvious dark spots and you can see some horizontal lines where the strips are. But [Zenodilodon] says the effect isn’t too bad in real-life, and considering it was a cheap TV the image quality was probably never that great to begin with.

On the flip side, if you find an LED TV or monitor in the trash with a cracked screen, it might be worth taking it home to salvage its super-bright white LEDs for your lighting projects.

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