Protect Your Coffee Machine With A Filter Monitor

June 9, 2019 by Jenny List 16 Comments

Coffee machines are delicate instruments, likely to be damaged by limescale. Thus they will often have a filter present, but filters have a limited capacity of water upon which they can be effective. At Make Bournemouth, they have approached the problem of when to change filters on their coffee machine by applying a bit of high-tech.

The water passing through the filter is monitored by a couple of DFRobot TDS modules, a flow meter, and a DS18B20 temperature sensor. The data from these is fed into an ESP32 dev board, which makes it available by a web interface for handy accessibility through a smartphone. It can then be used to work out how much of the filter’s capacity has been used, and indicate when a replacement is needed. All the code is available in a GitHub repository, and with luck now Bournemouth’s hackerspace will never see the coffee machine succumb to limescale.

Of course, this isn’t the first coffee maker water hack we’ve brought you. A year or two ago we told you about somebody making their pod coffee maker auto-fill too.

Panadaptors Didn’t Start With SDRs

June 8, 2019 by Jenny List 6 Comments

The must-have accessory on a modern all-singing, all-dancing amateur radio transceiver is a panadaptor. Inevitably driven by SDR technology, it’s a view of a band in the frequency domain, and it will usually be displayed as a “waterfall” giving a time dimension to see transmissions over a period.

[Bill Meara, N2CQR] reminds us that panadaptors are nothing new, indeed that they date back to the first half of the last century and don’t even need an SDR to work. And to prove it, he’s produced one for part of the 40-metre amateur band.

The principle behind an analogue panadaptor is simple enough, it’s a normal receiver whose local oscillator is given a linear periodic sweep over the desired frequency band and whose output drives the Y axis of an oscilloscope whose X axis is driven by the sweep. In [Bill]’s case the receiver is a BitX homebrew transceiver, and the swept local oscillator is provided by his Foeltech signal generator. A neat touch comes in the ‘scope being synchronised by triggering on a marker frequency at the bottom of the range being swept. He’s created a video showing it in action, which you can see below the break.

There are quite a few routes into making this type of simple spectrum analyser, indeed some of us have tried ti with TV tuners.

Continue reading “Panadaptors Didn’t Start With SDRs” →

Ask Hackaday: What Skills Would You Give A Twelve Year Old?

June 7, 2019 by Jenny List 84 Comments

In several decades of hanging around people who make things, one meets a lot of people fascinated by locks, lock picking, and locksport. It’s interesting to be sure, but it had never gripped me until an evening in MK Makerspace when a fellow member had brought in his lockpicking box with its selection of locks, padlocks, and tools. I was shown the basics of opening cheap — read easy from that— padlocks, and though I wasn’t hooked for life I found it to be a fascinating experience. Discussing it the next day a friend remarked that it was an essential skill they’d taught their 12-year-old, which left me wondering, just what skills would you give to a 12-year-old? Continue reading “Ask Hackaday: What Skills Would You Give A Twelve Year Old?” →

Spectrum Chiptunes On An STM

June 7, 2019 by Jenny List 5 Comments

Some of us here at Hackaday are suckers for a bit of chiptune music as the backdrop for many excellent times. The authentic way to create chiptunes is of course the original hardware, but in 2019 it’s far more common to do so with an emulator on a modern computer. That computer doesn’t have to sport a high-end processor and desktop operating system though, as [Deater] shows us with his ZX spectrum chiptune player on an STM32L46G Discovery board.

The impetus for the project came he tells us while teaching students to code simple sine wave music players, having code already in the bag for emulating the classic AY-3-8910 sound chip on the Raspberry Pi and the Apple II he decided to port that to the STM32L476 dev board. An earlier version used the internal DAC, but this was refined to send I2S data to an external DAC. The code can be had from GitHub (confusingly buried among code for an LED driver), and we’ve attached a video below of it playing some chiptune goodness.

Of course, Sinclair chiptunes don’t grab all the limelight. There have been plenty of Nintendo and Sega players too. You might also recognize [Deater] from his non-chiptune work, porting Portal to the Apple ][.

Continue reading “Spectrum Chiptunes On An STM” →

The UK Drone Community Fights Back, Gains FOI Admission Of No Tangible Drone Evidence

June 4, 2019 by Jenny List 33 Comments

Regular Hackaday readers will have noted a succession of stories following the reports of drones in the air over British airports and in proximity to aircraft. We’ve consistently asked for a better quality of investigation and reporting into these cases, because so far the absence of reported tangible evidence of a drone being present casts doubt on the validity of the official reaction. For too long the official records of air proximity incidents have relied upon a shockingly low standard of proof when apportioning blame to drone operators, and this situation has contributed to something of a panic over the issue.

It seems that some members of the British drone flying community are on the case though. Airprox Reality Check are a group analysing air proximity reports and linking them to contemporary ADS-B and weather records to identify possible explanations. They have devised a rating system based upon a number of different metrics in an attempt to quantify the reliability of a particular report, and they are tabulating their analysis of air proximity reports on a month by month basis. This includes among many analyses such gems as Airprox Report #2019046, in which an Embraer 170 flying at 9000 feet and 20 km offshore reported a drone in close proximity. The Airprox Reality Check analysis points out that no known drone could manage that feat, and refers to a passing Boeing 737 revealed through ADS-B data as a more likely culprit.

Their latest news is that they have made a Freedom of Information request to the Air Proximity Board, asking for what evidence the Board has of a drone having been involved in any of the over 350 incidents in UK airspace having been reported as involving drones. The official response contains the following quote:

in all cases UKAB has no confirmation that a drone has flown close to an aircraft other than the report made by the pilot(s). Similarly, other than from the report of the pilot(s), UKAB has no confirmation that a drone was involved.

This confirms the view of the multirotor and drone community that has been reported by Hackaday in the past, that the whole British drone panic has been based upon unreliable and uncorroborated reports from eyewitnesses with little direct experience of multirotors. If any irresponsible drone operator is flying into close proximity with aircraft or otherwise into protected airspace then it goes without saying that they should be prosecuted, yet it seems that the community is being punished as though this had happened when the reality is that no such acts are proven to have occurred.

C.H.I.P. Or Z.O.M.B.I.E? We Can’t Decide

June 4, 2019 by Jenny List 58 Comments

Imagine for a moment that you are back in 2015. Radio Shack are going to the wall, Heathkit returning from the dead, and Arduino spliting into two warring Arduinos. And someone has announced a tiny Linux-capable microprocessor board called the C.H.I.P. that will cost only $9. We all thought that last one was pretty cool at the time, didn’t we. Then Heathkit’s new products turned out to be pretty lacklustre, the warring Arduinos merged, and the C.H.I.P? The consensus was that $9 was a tall order for that BoM at the time, and then the Raspberry Pi people gave away a free Pi Zero on the front of a magazine before selling it for £5 ($6.30). It didn’t matter that the C.H.I.P. had a nifty all-in-one screen and keyboard combo called the Pocket C.H.I.P. which was a significant object of desire, the venture lasted for three years before finally hitting the rocks last year.

Now the C.H.I.P. is back, in a crowdfunding campaign fronted by one of its original engineers. It’s been renamed the Popcorn, and it comes in three variants. The Original Popcorn is a compatible C.H.I.P. by any other name, while the Super Popcorn is a much higher-spec machine that comes in quad and octacore variants with AmiLogic SoCs. All three have 32 GB eMMC on board, and the specs are suitably impressive but not out of the ordinary for a 2019 single board computer. Prices are $49, $69, and $89, which takes away that optimistic $9 price tag that made the original so attractive. There is no Pocket C.H.I.P. which is a shame because for us that was the only reason to buy a C.H.I.P, but there is a companion board called the Stovetop that provides Raspberry Pi-style desktop and display interfaces.

We wish them well, but it’s difficult to escape the conclusion that the hardware world has moved on and the window of opportunity has closed. It’s not that these boards are not good ones, more that they now join a plethora of others which come a lot closer to the low price of the original. Still, there remains a C.H.I.P. community still out there, so perhaps that will save the day for them.

We interviewed the C.H.I.P.’s creators back in 2015, and marked its passing last year.

Thanks [Rose] for the tip.

Building An Ergonomic Keyboard

June 3, 2019 by Jenny List 19 Comments

Despite the passing of several decades since that scene in Star Trek IV, the Voyage Home in which Mr. Scott remarks “A keyboard! How quaint!“, here on earth, they remain a central plank of our user interface experience. A plank is an appropriate metaphor, for the traditional keyboard with its layout derived from typewriters and intended to minimize type bar collisions has remained the same flat and un-ergonomic device for well over a century. If like [Tom Arrell] you suffer from repetitive strain injury to your hands and wrists from using a keyboard then a more ergonomic alternative is a must. His solution was to build his own keyboard in two halves.

He was inspired by a colleague’s Ergodox, but balked at the price. Then he found the Dactyl, an open source 3D printed keyboard in two halves, and resolved to build his own. Unlike the Dactyl, however, he wanted his ‘board to be able to operate as either a linked pair operating as one or a pair of separate keyboards. In went a pair of Sparkfun Pro Micro boards to his slightly modified Dactyl, along with a full complement of Cherry MX Brown switches.

The final product lacks key labels so is not for the faint-hearted. But he persevered with it and after a couple of weeks was able to use it without a crib sheet. It’s a bit higher than its commercial equivalent so it needs some improvised wrist rests, but for the price, he’s not complaining.

This isn’t the first keyboard with two halves we’ve shown you, here’s one from 2017.

Via Hacker News.