Black Graphics On Your TV, For A Greener World?

August 14, 2023 by Jenny List 95 Comments

Can you really save energy by carefully choosing the colors displayed on a TV screen? Under some conditions, yes. Or at least that’s the conclusion of a team at the BBC that looked at reducing the energy consumption impact of their output by using what they call Lower Carbon Graphics. In short, they’re trying to ensure that OLED displays or those with reactive backlights use less energy when displaying BBC graphics, simply by using more black.

It turns out that a lot of British households play radio stations on their TVs, and the BBC sends a static image to each screen in this mode. As part of a redesign across the organisation, the BBC removed the bright background colours from these images and replaced it with black, with a remarkable reduction in power consumption, at least on OLED and FALD screens. (On normally backlit screens, 89% of British TVs, this does nothing.)

If you look hard at their numbers, though, listening to radio on the TV is horrendously inefficient; can you imagine a radio that consumes 100 W? If the BBC really wants to help reduce media-related energy consumption, maybe they should stop broadcasting radio programming on the TV entirely.

Anyway, as we move toward a larger fraction of OLED screens, on TVs and monitors alike, it’s fun to think that darker images use up to 40% less power. Who knew that Hackaday was so environmentally friendly? Black is the new green!

Header: RIA Novosti archive/ Igor Vinogradov, CC-BY-SA 3.0.

This 3D Scanner Uses A Sensor You Might Not Know About

August 14, 2023 by Jenny List 24 Comments

The huge diversity of sensors and other hardware which our community now has access to seems comprehensive, but there remain many parts which have made little impact due to cost or scarcity. It’s one of these which [Enginoor] has taken for the sensor in a 3D scanner, an industrial laser displacement sensor.

This sensor measures distance, but it’s not one of the time-of-flight sensors we’re familiar with. Instead it’s similar to a photographic rangefinder, relying on the parallax angle as seen from a sensor a distance apart from the laser. They are extremely expensive due to their high-precision construction, but happily they can be found at a more affordable level second-hand from decommissioned machinery.

In this case the sensor is mounted on an X-Y gantry, and scans the part making individual point measurements. The sensor is interfaced to a Teensy, which in turn spits the data back to a PC for processing. By their own admission it’s not the most practical of builds, but for us that’s not the point. We hope that bringing these parts to the attention of our community might see them used in other ways.

We’ve featured huge numbers of 3D scanners over the years, including a look at how not to make one.

Home Network Organization Gets Out Of Hand

August 14, 2023 by Chris Lott 59 Comments

[SpookyGhost] has a big home network, and has taken cable management and server organization to the extreme. He has written about individual components before, but this blog post brings it all together and reviews the entire system. The networking gear is installed in a closet and mounted in a 25U tall 19-inch rack. From top to bottom, here is a brief list of the gear:

Keystone patch panels
pfSense Firewall / Router
Two Cisco Ethernet switches
Redundant internet connections
Shelf of numerous servers
RAID-Z2, 12 each 8 TB SCSI, media storage
NAS RAID, 6 ea 4 TB SAS, 2 ea 800 GB SSD
Video Management System, 48 TB storage
UPS and power distribution units

Most of the Ethernet uses 10GBASE-T and Cat6 cabling and connectors, with some interconnects use fiber optical cable and LC connectors. Unsurprisingly, as this setup grew and grew, [spooky] had to pipe in air-conditioning to the closet.

This is a serious installation, but there are plenty of good ideas for folks with less ambitious networking goals and/or requirements. We liked the swappable Keystone jacks in the patch panels, and the cable pass-through panel with a dense curtain of rubber fringe to keep things looking tidy. If you have any ideas to share on network equipment and cable management, let us know in the comments.

Linux Kernel From First Principles

August 13, 2023 by Al Williams 13 Comments

Want to learn the internals of the Linux kernel? Version 6.5-rc5 has about 36 million lines of code in it, so good luck! [Seiya] has a different approach. Go back to the beginning and examine the 0.01 version of the kernel. Now you are talking about 10,000 lines and, removing comments and blanks, way less.

Sure, some things have changed, but the core ideas are the same. [Seiya] reports, “Reading V0.01 was really for me. It was like visiting Computer History Museum in Mountainview…”

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Update Your Chinese Radio Without The Pain

August 13, 2023 by Jenny List 44 Comments

The new hotness in cheap radios this year has been the Quansheng UV-K5, a Chinese handheld transceiver with significant RF abilities and easy modding. The amateur radio community have seized upon it with glee and already reverse-engineered much of the firmware, but flashing the thing has always required a minor effort. Now thanks to the work of [whosmatt], it can be flashed with little more than a web browser and a serial cable.

This feat was made possible through the magic of WebSerial, a handy feature that allows web applications to talk to connected hardware. We’ve seen it in action a few times in the world of badges, and as browser support for it has improved it’s now available through browsers on all the major platforms.

The web app allows tweaking of the Quansheng settings and will, no doubt, be capable of uploading that when fully open-source firmware is available. It should be of great interest well beyond the world of Chinese radios, though, because we’re guessing there are a lot of projects that could benefit from such a ubiquitous interface tool.

If you’d like to know more, WebSerial is something we’ve looked at in the past.

Header image: [Concretedog]

Hackaday Links: August 13, 2023

August 13, 2023 by Dan Maloney 14 Comments

Remember that time when the entire physics community dropped what it was doing to replicate the extraordinary claim that a room-temperature semiconductor had been discovered? We sure do, and if it seems like it was just yesterday, it’s probably because it pretty much was. The news of LK-99, a copper-modified lead apatite compound, hit at the end of July; now, barely three weeks later, comes news that not only is LK-99 not a superconductor, but that its resistivity at room temperature is about a billion times higher than copper. For anyone who rode the “cold fusion” hype train back in the late 1980s, LK-99 had a bit of code smell on it from the start. We figured we’d sit back and let science do what science does, and sure enough, the extraordinary claim seems not to be able to muster the kind of extraordinary evidence it needs to support it — with the significant caveat that a lot of the debunking papers –and indeed the original paper on LK-99 — seem still to be just preprints, and have not been peer-reviewed yet.

So what does all this mean? Sadly, probably not much. Despite the overwrought popular media coverage, a true room-temperature and pressure superconductor was probably not going to save the world, at least not right away. The indispensable Asianometry channel on YouTube did a great video on this. As always, his focus is on the semiconductor industry, so his analysis has to be viewed through that lens. He argues that room-temperature superconductors wouldn’t make much difference in semiconductors because the place where they’d most likely be employed, the interconnects on chips, will still have inductance and capacitance even if their resistance is zero. That doesn’t mean room-temperature superconductors wouldn’t be a great thing to have, of course; seems like they’d be revolutionary for power transmission if nothing else. But not so much for semiconductors, and certainly not today.

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Portable 1990s POS Will Strain Your Back

August 13, 2023 by Chris Lott 4 Comments

[JR] over at [Tech Throwback] got ahold of an unusual piece of gear recently — a portable Point of Sale (POS) credit card machine from the late 1990s (video, embedded below the break ). Today these machines can be just a small accessory that works in conjunction with your smart phone, but only the most dedicated merchants would lug this behemoth around. The unit is basically a Motorola bag phone, a credit card scanner, a receipt printer, a lead-acid battery, and a couple of PCBs crammed into a custom carrying case

Despite having a lot of documentation, [JR] struggles to find any information on this U.S. Wireless POS-50. He finds that the credit card scanner is an Omron CAT-95 authorization terminal, and the Motorola SCN-2397B phone appears to come from the Soft-PAK series.

He is able to power it up, but can’t do much with is because he is missing the authorization password. But regardless, with the demise of the Advanced Mobile Phone System for over a decade, this 850 MHz band analog phone can’t connect to the network anymore.

If you happen to know anything about this old POS, or used a similar luggable system for accepting credit cards in the 1990s, let us know in the comments below.

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