[Colin] has put together an instructable for a solar power generator that uses the thermoelectric effect instead of the photovoltaic (PV) effect. We have seen Peltier devices used in cooling cans, solder paste, backs, and hacked hard drives. This is the first hack we have seen where a Peltier device is used to generate electricity from heat, essentially running the device backwards. The thermoelectric effect is the same principle that is used to generate electricity in radioisotope thermoelectric generators used in deep space probes such as Cassini. What applications can you come up with to use the thermoelectric effect as a power source?
This really cool project allows a grand piano to “speak”. We don’t know any details about its construction but we had to share. The keys are being hit by solenoids in a manner to replicate human speech. Click through to the video, it’s worth it. You may have to allow the popup to see the video, and it is in german, but the piano is clearly speaking english. We want one to keep around the office. It could read our emails to us.
(Edit from 2015: The link went bad, but it can be found elsewhere on YouTube.)
Reader [Mikey Sklar] told us about a review he wrote covering 3 different models of pocket multimeters. We’re sure that you’ve had the same experiences we have being the go-to-guy or got-to-gal for all things electrical. For our sort, having a multimeter on hand at all times has become an expectation.
[Mikey] looks at a model from ebay, Harbor Freight, and Radio Shack. Not surprisingly, the ebay offering doesn’t rate too well but does get the job done. We were surprised to read that he picked up the Cen-Tech model for about $10 at Harbor Freight. Although it may no longer be sold there (we haven’t checked) [Mikey] seems pretty happy with it so we’ll be on the lookout during our next tool-buying trip. We’re unfamiliar with the tiny Radio Shack 22-820 but we’ve always been happy with our larger 22-811. The 22-820 allows the probes to be folded up inside of the case cover for a truly pocketable package.
You can never have too many meters at your disposal and we’ll have to keep this article in mind the next time we’re shopping for another. Never used a multimeter before? Take a look at the tutorial [Mikey] linked to over at ladyada.
[Jenn’s] family is a single-car household. Because of this, it’s a little more difficult to get a jump start when the headlights run down the battery. Not wanting to ask the neighbors for help, her husband [Richard] decided to come up with his own solution.
Rummaging through the parts on hand, [Richard] went with his old friend Sonic the Hedgehog. He used two 12-volt, 1 amp Sega Genesis power adapters in parallel hooked up to a 12 volt, 3 amp power supply. The end result is a 12-volt 5 amp source hooked to the car’s electrical system and used to get their road machine started.
We have enjoyed some of [Richard’s] offerings in the past, such as Super Nintoaster and the Super Genintari but this is a bit less… eloquent. A few questions do come to mind. First of all, is this the best way to use parts of your 20-year-old gaming system? How many amps does your average car starter pull down? And finally, what kind of issues are we looking at with the lead acid battery under these conditions? Weigh in on the conversation in the comments.
[Backroads] has put together this nicely detailed writeup explaining how to make a low cost popup prop. He’s using a single pneumatic valve and a home made PVC piston to raise and lower a scary mask. He’s using an off-the-shelf 110v AC valve controller to control the valve. A flickering light, a “screamer” and a fog machine help fill out the project. The result is quite nice. We would be tempted to put a pressure sensor in front of it to optimize the scare timing.
[Linuxworks] has posted a writeup on how to build an IR module for the popcorn hour c-200. We weren’t familiar with the popcorn hour c-200, so we had to look it up. It seems to be a media center pc sort of thing. We’re not reviewing the unit itself, since we’ve never used one, so we’ll just get back to the mod. The device uses an RF remote, which some people didn’t like as much. Luckily it has an expansion port which can be utilized to get IR signals into the machine. [Linuxworks] has used a cheap IR sensor and a standard headphone plug. He notes that equipment passing power through these plugs should be turned off before plugging them in or removing them as they short momentarily during insertion.
We’ve seen a lot of the Monome, a USB based controller often used as a sampler, here at Hack a Day. This is one of the more creative hacks. [brothernigel] took a Monome 40h kit and fit it inside the case of a vintage radio. The faceplate was a custom order to fit his purposes and incorporates the original radio frequency display. The USB port was well placed in the side of the wooden housing. For extra “soul”, pen and ink art adorns the insides. His work log gallery takes you through the process from start to finish.
We never noticed before, but the Monome makes a great vintage-looking-electronics project. All the lighted buttons are straight out of a ’60s military command center.