The Raspberry Pi foundation is in a somewhat unique position. They always test the units that get returned to them in hopes that they can improve the design. They often request that the power supply also be sent back with the RPi unit, as we know the board will not work well if the PSU can’t source enough current. And so they’ve been able to get a look at several counterfeit iPhone chargers. This is not one of the recommended ways to power the RPi, but their ability to collect failed hardware means that they have identified three different fakes on the market.
Seen here is a genuine Apple product on the left. The others are fake, with the easiest way of spotting them being the shiny chrome plug connectors. The genuine part has a matte finish on the connectors. There is also a difference in the chamfering, and even a variation on the orientation of the USB port on some of them. Unfortunately we don’t get a look inside, which is what we really wanted. But you can see in the video after the break that weighing the adapter will also give it away as a fake, showing that the components within probably vary quite a bit. This reminds us of some other fake PSUs that have been exposed.
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This lens adapter makes a lot of sense if you’re looking to interface with cameras that don’t have an in-built mounting option. It uses the cap and threaded neck from a soda bottle (translated) to make the lens adjustable and removable.
In the past we’ve seen this hack using a lens cap with a hole drilled in it as the mounting bracket. But that’s only useful if the lens you’ve chosen actually has a cap to use. This method lets you cut the top off of a the soda cap and mount it on the camera. Now each lens can be affixed to the threaded neck of the bottle, allowing for some adjustment of the focal point by screwing the add-on in or out.
Obviously this would work well for macro or fish-eye lenses. But there’s all kinds of other options out there like adding a microscope lens adapter, or actually attaching quality optics to your device.
[devb] has been playing around with XESS FPGA boards for ages, and as long as he can remember, they have had built-in VGA interfaces. His newest acquisition, a XuLA FPGA board, doesn’t have any external parts or ports aside from a USB connector. He needed to get video output from the board, so he decided to build a VGA interface himself.
He prototyped a 512-color VGA interface board which worked just fine, but he thought it would be way too cumbersome to use for each and every project. To keep life simple, he designed a small PCB that integrates a VGA connector and all of the resistors he needed to get the signal from the FPGA. His boards plug directly into a breadboard, so only a handful of wires is needed to connect the FPGA to a monitor.
As you can see on his site, the adapter works quite well, allowing the FPGA to put out a crisp 800×600 image with little fuss. [devb] has also posted all of his design files on his site in Eagle format for anyone interested in replicating his work.
[Kusnick] is into using digital camera rigs for book scanning. The problem is that keeping the batteries charged is a pain, but there’s no external AC adapter jack which would allow him to use the mains. His solution was to build his own adapter to replace the batteries.
There are some fancy book scanning setups that allow you to just flip through the pages, but it’s much simpler to build a rig that uses two cameras. [Kusnick’s] setup is the latter, which means he’s found two inexpensive cameras that don’t need to be mobile. The first attempt at making an adapter featured a block of acrylic with the positive and negative contacts connected to a shielded cord which he then hooked to an external supply. The camera would come on and then turn off citing that the cameras were “for use with compatible battery only”. Turns out there’s some type of verification circuit built into the proprietary batteries. But the solution to that came quite easily; remove the circuit board from the battery and insert it in the adapter to trick the camera.
[Devon Croy] built a case to join a webcam sensor with a camera lens. The box is a PVC conduit box you’d find at a home center. He used JB Weld to attach four bolts to the back of the box. These are used to fine-tune the mounting plate for the webcam sensor to ensure it’s at the focal point of the lens. The lens connects through a couple of extension tubes to an adapter mounted in the center of the box’s cover plate. The setup above shows a macro lens that takes pretty good pictures.
If you need images of really tiny things you should look into a microscope adapter for your camera.
[Ben Krasnow] is capturing some great snapshots using a microscope adapter and some tricks. The camera attachment is just a lens adapter ring with a tube added. Unlike other microscope imaging hacks we’ve seen he used a real microscope but found that the pictures had a bit of light distortion to them. The camera sensor was picking up a glare reflected on the inside of the black tube. By adding a washer and repositioning the apparatus he got over that hurdle. The final part of the puzzle is image processing. By taking several pictures at different focal lengths and compositing them he gets killer photos like the compound eyes of that house fly seen above.
[Mark Bog] thought it was a waste to use batteries for his desktop touch pad. Quite frankly we agree that if you can avoid using disposable cells you should. He ditched the dual AA batteries inside of his Magic Trackpad and built a battery-sized adapter to feed it some juice. It consists of a dowel of similar diameter with a screw in each end. He scavenged a USB cord, connecting hot and ground wires to the corresponding pole of the adapter. Now his Trackpad is USB powered and never in need of a battery replacement or even a recharge.
We’re not familiar with the inner workings of Apple’s Magic Trackpad. We assume there’s a voltage regulator inside and we hope it doesn’t have a problem working with the 5V regulated power coming in from the adapter. If you’ve got the skinny on the hardware we’d love to hear about it in the comments. One last thing: because the forum linked above requires a login to view the images in the post, we’ve embedded the rest of them after the break for your convenience.
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