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GPS modules are coming down in price, with cheaper units made overseas being available for under $10. However, they come with some disadvantages. They typically have lower accuracy, and worse reception. This means it takes a lot longer to get an initial fix, like the GPS receivers from the 1990s which needed an open sky and many minutes.

But a recent chipset from Mediatek has improved in both areas. It is more accurate and more sensitive. This GPS receiver board from elektronic-idee pairs the new Mediatek MT3333 chipset with a beefy antenna connector. With the included antenna, it’s possible to get decent GPS reception indoors. This makes it an ideal partner to a GPS-disciplined clock source for your home lab. Even a high-quality rubidium oscillator can be improved by adding GPS discipline. You will see an even bigger difference when pairing it with either a temperature compensated or oven controlled quartz oscillator. (Psst, the same seller actually sells a pre-made GPS-disciplined oscillator that integrates this same GPS chipset!)

This receiver supports 33 channels of tracking with 99 channels for acquisition. It supports both GPS and GLONASS, as well as various SBAS (Satellite-based Augmentation Systems) which can, in certain parts of the world, give more accurate location fixes and timing outputs. In this category, it supports both current and future American, Japanese, and European augmentation systems.

It can give accurate position data using as little as 7mA! Even in full-power tracking mode, the GPS module only uses 23mA. This is an order of magnitude better than older generation chipsets, and can dramatically increase battery life. This makes options like solar or energy harvesting viable.

The chipset boasts an active interference canceller, and a built-in logging function. This is the perfect chipset to use in low-power IoT solutions that need location data. As a bonus, the seller includes an active GPS antenna which supports 3.3 or 5V (though the board itself runs at 3.3V) that will improve signal reception. Compared to passive antennas, the difference can be amazing, especially when indoors or when line-of-sight to the sky is impeded.

If you’ve been looking for a low-power, high-accuracy GPS receiver, or if you’ve been wanting to add GPS discipline to your lab oscillator, this board is a great choice!

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Ah, USB Power Delivery, my favourite part of the new USB-C specification. Finally, high-speed charging through reversible USB cables! It’s great to see more hackers using USB PD in their USB-C designs, and this is a nifty little charging upgrade for Lenovo Thinkpad laptops. The downsides of older laptop charging systems are having a proprietary cable, and the fragility of barrel connectors over time. Using USB-C as a laptop charging cable is a great idea, which many modern laptops have started to incorporate. But why not bring that new technology to existing laptops?

Many laptops end up with broken or worn-out charging cables (you should see mine — it’s a big mess of heat shrink and hot glue). A replacement power supply from the manufacturer can be as much as $150! Using third-party power supplies is possible with some manufacturers, but my Dell laptop has a secret serial connection to the charger, which it uses to query and find out if the charger is genuine. If it doesn’t respond, or if the cable breaks (grumble grumble) the laptop will run at a reduced clock speed, and it won’t charge the battery. What a pain!

Luckily, Handy Tools of Taiwan has created this replacement module that converts a range of laptop charging ports to USB-C. It is aimed at the Thinkpad X220 and X230, but there are a variety of different Lenovo laptops that use the same power connector. Be sure to check the power rating of your existing power brick and order the correct replacement! You will also need to pick up a USB-C wall adapter that supports Power Delivery at the voltage and current your device needs. These are becoming more common, and prices are falling, so that shouldn’t be too difficult! Note that Handy Tools also offers a similar replacement module for another range of Lenovo laptops. Very cool!

If you are curious about the Power Delivery spec, I highly recommend checking out the USB Implementer’s Forum PDF about Power Delivery. It’s amazing to me that they have released this spec for free — no yearly fees for access to their specs! This enables hackers like Handy Tools to easily create devices which can interface with existing USB PD chargers and take advantage of their flexible output voltages.

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Power banks are ubiquitous, and because they offer 5V with an easy to use USB port, they often find use in wireless projects. IoT projects in particular often take advantage of the high power density and small form factor. But most power banks have a feature to turn themselves off when the attached device (presumed to be a phone or other device that requires charging) reaches full charge. They do this by sensing the current draw, watching for it to fall below a certain threshold.

This can be a major issue for projects with a low, steady standby current, which also need bursts of high current when transmitting. This smart device helps keep your power bank from switching off when your device is not drawing much current — and it does it without drawing excessive power!

This design takes advantage of the fact that before shutting off due to low current draw, power banks have a delay of 5-10 seconds. By drawing very small pulses of current every few seconds, the circuitry is kept awake. The amount of energy actually used is completely configurable, depending on your individual power bank. You can have it draw up to 140mA for any length of time, at intervals which are also customizable. This allows it to be used with a wide variety of power banks.

Sure, some power banks don’t have this feature, or might have a cutoff which is below what your device draws. But finding the perfect power bank could be a costly and difficult endeavour, when you can just use whatever power bank is the most economical paired with this device!

The source code and design files are freely available for modification from GitHub. Happy hacking!

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Wireless projects using the popular nRF24L01 transceivers are popping up everywhere. They are easy to configure, low-power, and reliable over surprisingly long distances. This tiny development board pairs the nRF24L01 with an STM32 microcontroller for a compact and easy to use platform!

This board features the STM32F042G6U6, a low-power ARM Cortex-M0 microcontroller from ST with 32kB of flash and 6kB of RAM. It can run at up to 48MHz, which is incredible for its low power consumption. It’s absolutely packed with peripherals, and development toolchains are freely available for all operating systems. The integrated bootloader means it can be programmed directly via the USB port, without the need for an external programmer — however, the SWD pads are also broken out in case you want to connect your existing debugger, or program your own bootloader. The high-speed SPI paired with DMA means you can easily keep up a high-speed data link.

An excellent addition to the board is the footprint for the RFM69, a different wireless transceiver that uses either the 868 or 915MHz bands, depending on your location. While this board currently is only available with the nRF24L01, having more development options is always nice.

This board can be used as a stand-alone project development platform, or used as a wireless base station to communicate with other devices in the field. It is useable with small single-board computers like the Raspberry Pi or BeagleBone Black, opening up a huge range of possible applications. The included clear Gainta enclosure is a nice touch — development boards with enclosures always seem to last longer (especially in my lab!).

If you’ve been wanting to play with the nRF24L01, this is the perfect board to get you started. Check out the System Workbench for STM32, a free IDE from ST that works on Windows, Mac and Linux. It’s a great way to get started. The source code and design files for this board are also freely available. Happy hacking!

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RF still seems like a black art in many ways to me. When you look at the surface of this antenna, the mind simply boggles — how can this work as an effective antenna, especially across such a wide frequency range? Well, this 300MHz-3GHz Log Spiral Antenna might just be the perfect antenna for applications like LoRa, Bluetooth, and other ISM band applications.

For those of you not familiar with LoRa, it is a low-power wide-area network specification. It uses the ISM sub-gigahertz bands, meaning users don’t need a license to operate it. It can be very efficient over surprisingly long distances. It has proved extremely popular in IoT projects, especially those located outdoors, as the low power requirement fits perfectly with embedded devices. They form a network which reports back to a base station — a role this antenna would be perfect for.

The antenna was tested by a company called AntennaTestLab. The above image is the antenna being tested in their anechoic chamber! The results were very interesting. This animated GIF shows a Smith chart of the results by frequency — and I’m not ashamed to admit I spent far too long staring at it! I’m far from an RF expert, but I found it very interesting to note that the two polarizations are not always mirror images of each other. If you’re interested, Hex and Flex (the designer) has a lot more information about the test results on their website.

Of course, it also covers the 2.4GHz ISM band, which means it could be used as a bidirectional WiFi or Bluetooth antenna. While it doesn’t have a lot of gain at 2.4GHz, the directionality could be used to help cover a part of your home or property that isn’t reached well by your router. This antenna is also great for Global Navigation Satellite System (GNSS) applications, such as GPS, GLONASS, Galileo, and BeiDou.

And finally, it just looks super cool! If you want to give a wireless project a bit of extra flair, having a cool looking antenna can be just the touch you need. Family and friends will be sure to ask “What the heck is that thing?!” every time they visit.

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If you use computer-aided design (CAD) software often, you know how many keyboard shortcuts there are to remember. Plus, power users often create macros to do repetitive tasks. What if you had a separate keypad that could simplify these shortcuts, while also knowing exactly which program you are in and which shortcuts you want at that time? The Hub16 Programmable Macro Keyboard ticks those boxes and more! With 16 keys and two rotary encoders, you can have quick, fine control over your designs.

However, it certainly isn’t limited to CAD software. Another great use case would be for digital audio workstations (DAWs) which have the similar problem of a million keyboard shortcuts and a complex graphical interface. Knobs would come in especially handy in this scenario for scrubbing across a timeline or changing audio input parameters.

Of course, it has the RGB LEDs for bling factor, but they can also be used to inform the user which context they are in, and what functions are currently assigned to the keypad. Perhaps you could have blue for Kicad PCBNEW, red for eeschema, and yellow for Adobe Premiere. The customization options are endless!

However, I think the feature that really puts this on my wanted list is the built-in USB hub. What a smart thing to add to a device that is sitting on your desk! And even better, it uses USB Type-C which is quickly becoming the standard for all modern devices. You could have your graphics input tablet connected, and have the Hub16 sitting beside it for quick keyboard shortcuts — leaving your main keyboard to the side entirely. Or you could connect your audio controller, allowing you to tweak and play with sounds and clearing space on your desk for a full-sized MIDI keyboard.

The only downside is that the switches are not included. This is understandable, as people who use mechanical keyboards often want to use their favourite keyswitch, and stocking that many different options would be a pain on a small project like this. Perhaps down the line we will see it come pre-assembled, but with its current focus on the CAD market we think any current customers would have no problem sourcing and soldering their keyswitch of choice. This also allows you to customize the keyswitches, so you could have lighter touch keys in certain positions for repetitive tasks, for example.

Whatever the use case you decide on, make sure to check out the excellent build instructions and software configuration documentation.

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If you are into hardware hacking in any shape or form, having a handy power supply with which to power your latest prototype can be a real pain. Well, this tiny, USB-powered board can provide your project with up to 20 V! How are they pulling this off in such a tiny form factor?

With the release of USB Type C, the USB Implementers Forum created a standard called Power Delivery, which allows devices to charge at higher voltages and currents than the previous standards allowed for. Modern smartphones and laptops have started to take advantage of this, and are able to charge much faster due to the increased power available. Chargers which support Power Delivery can provide 20V at up to 5A (100W!) which is more than enough to charge the average laptop.

However, the charger won’t provide this extra power unless it is asked for, in order to maintain backward compatibility with older 5V-only USB equipment. To take advantage of this feature, you need a way to communicate with the charger over the new CC1 and CC2 lines in the USB-C cable. Once the attached device has asked for a higher voltage, the charger changes modes and delivers the requested voltage on the Vbus line. Not all chargers support all power levels, though. A charger can be Power Delivery compliant but only supply, say, 9 V at 3 A. This is plenty for the average smartphone, but just keep it in mind when you are choosing a charger to use with this board. So, the USB-C PD Sink is simply taking advantage of modern chargers with Power Delivery in order to provide a variable voltage power supply for whatever you want!

With just a compliant USB-C Power Delivery charger and the USB-C PD Sink, you can quickly and safely get enough power to keep all your projects moving! You can charge your quadcopter, or power your latest evil robot prototype — we won’t judge. The beauty of using a higher voltage is that you end up with less power dissipation in the cables, meaning more juice available for your project. It’s a win-win!

If you are interested in learning more about Power Delivery, the USB Implementers Forum has the full specification available on their website. It’s quite dense, and full of a lot of technical lingo, but it’s excellent that it’s freely available for us to learn from.

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Lithium polymer and lithium ion batteries — like all rechargeable batteries — have a limited lifespan determined by the number of charge/discharge cycles. Leaving your phone plugged in all the time increases the strain on the battery, reducing its useful lifespan and wasting energy. The ProCharge goes in-line with your charge cable, and automatically delays and monitors charging of your device. This way, you still wake up with a fully charged phone, but you’ve reduced the strain on the battery and saved some energy by not powering the phone at idle all night!

There are software solutions available for both major phone OSes, but they cannot actually stop the phone from charging — they merely remind you to unplug the phone when it hits a certain charge percentage. This can also protect the battery, but you end up without a fully charged phone, and if you fall asleep before the notification goes off, it’s useless. Having a hardware solution like this is much more reliable, and doesn’t require user intervention, which means you’re more likely to actually see results!

This graph shows the potential energy savings. By delaying the charge cycle, you are saving energy, which adds up to about 90 days per year that you aren’t charging your phone!

Because smartphone manufacturers are aware of the limited lifespan of lithium batteries, they have attempted to mitigate these issues in software. The phone can detect if the voltage starts dropping quickly when current increases — the sign of a weak or nearing end-of-life battery — and it responds by lowering the clock speed of the CPU. This leads to the device acting sluggish and often causes stability issues. However, if the phone continued to run at full speed, it would quickly drop the battery below its cutoff voltage and the phone would just shut off. Apple was vilified in the media a while ago for slowing down their older phones, but I suspect it was just this mechanism in action. They were trying to preserve what little battery health the phones still had left!

Check out the product page and learn more about how the ProCharge works. It wouldn’t surprise me to learn that the ProCharge could add months to the lifespan of a smartphone battery!

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Arcade machines were overwhelmingly made by Japanese companies, which is why the standard they ended up using (JAMMA) was named after the Japan Amusement Machine and Marketing Association. This jam-packed PCB called the PARSEC Supergun allows using JAMMA PCBs outside of an old-school arcade cabinet. That means megafans of coin-op can play classics like the original Double Dragon II arcade game on a TV.

This is possible because of the aforementioned standard — though the games varied, the interfaces they used to connect to the display and controls remained the same. This allowed, for example, Donkey Kong machines to be turned into Donkey Kong Jr. machines. The nickname given to this type of device in the arcade community is a “SuperGun” — thus the name PARSEC SuperGun.

This compatibility is made even more convenient for home use with the PARSEC. All it needs is a standard ATX power supply, the JAMMA board you want to play, some sort of compatible input (Neo Geo controllers work), and a sound/composite display output. Presto! You can impress your friends by having the real deal running in your living room, and not an emulated machine like most modern cabinets use. It seems that customers love it too, as this product has a 5-star review rating on Tindie!

Tindie seller Low Budget have even included optional “hats” for VGA (with both composite and TTL output options), as well as component video. The JAMMA connector has the Japanese characters thoughtfully printed on it to make setup easier — a very nice touch. The standard board also has buttons to put the game into service or test modes — so you can play for free! You can, of course, attach a coin collector if you want your friends to bring quarters every time they drop by.

Here is the designer showing off an earlier (v1.0) revision of the board:

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The Amiga 500 was an extremely popular personal computer that Commodore introduced in the late 1980s, and this replica Amiga motherboard could be the key to fixing broken ones! Commodore’s Amiga line of computers competed directly against both Atari’s ST line, and the IBM PCs and clones. Those who used Amigas truly loved them — in fact, there are still many Amiga users today. Some people are even still running bulletin board systems using Amigas!

The need for this replacement board arises from a common foe of many retro computers — the dreaded leaky backup battery. Most computers of the time had lithium rechargeable cells on-board to keep time and date, as well as BIOS options. Unlike modern computers which use easily replaceable CR2032 batteries, older machines would often use batteries soldered directly to the board, or odd batteries that were difficult to replace. To top it all off, many would forget about these batteries when storing their old computers. Twenty years later, they open the case and the acid has leaked, causing extensive, often irreparable damage to both the PCB and the components on it.

A PCB this size is no small feat and we commend Bob’s Bits for taking it on! He has also added many improvements, including better and more understandable silkscreen identifiers and quality-of-life improvements for the end user. If you’ve been looking to restore a damaged Amiga 500, this could be your ticket! Or it can be used to build the new and improved A500++ as seen in TheRetroManCave’s video below. We haven’t seen many products focused on the Amiga computers, and we’re very glad to see this one; hopefully it inspires others to take a look at these awesome classic computers.

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