Although now it’s impossible for a DIY nut to build electronics for less money than a factory, this wasn’t always the case. For 45 years, Heathkit produced inexpensive kits for just about everything. Heathkit closed it’s kit business in 1992, but now they’re back. They’re starting out with a few DIY kits at first, namely an ultrasonic garage parking assistant and a wireless swimming pool monitor.
Heathkit is calling all builders to submit their ideas for future kits. While this comeback rings of some other outlets with a rich heritage, Heathkit is still remembered fondly; Barry Goldwater jetted out to the Heath HQ twice a year for kits. Not many people are that attached to Realistic and Optimus gear.
If you’re wondering about the kind of stuff Heathkit offered, feel free to check out the 1984 catalog that features computers with 128kB of RAM available for only $1899.00 (yes, a very competitive price)
Tip ‘o the hat to [Jeffrey Bail (N1BMX)].
After seeing many projects that use microcontrollers to switch mains voltages [Rob Miles] decided to share his preferred method. The shots you see above are an enclosed relay, part number RIBTU1C manufactured by Functional Devices Inc.
This in itself is not the full control scheme that he uses, but it takes care of the bulk of the hardware. He uses a triggering circuit based on a 555 timer (PDF). [Rob] mentioned that if you shop around, you can get the relay, 555 timer, and other components for under $15. This is a great solution for the money when you consider that you get an enclosure meant for handling high voltage and a nice terminal block to which you can connect the mains wiring. The relay itself can be triggered by a 9V battery via the transistor in the control circuit.
Notice the protoboard in the image above. There’s plenty of room for your driver circuit to rest inside the box, protected by that barrier from the HV circuitry. Check out the rest of the images he sent us after the break.
Continue reading “High Voltage: Using enclosed relays for HV switching”
It looks like Radio Shack is pretty serious about their new found commitment to their focus on the DIY, inventor, creator and geek demographics. [Ken Gracey], Parallax forum guru, put up a post on the Parallax stuff that will be sold at Radio Shack. Everything is priced, “below spousal approval level,” but no word on what those prices are.
Here’s the (probably not conclusive) list we gleaned from the pics: 2-axis joystick, gyroscope, GPS, compass and altimeter modules, an infrared sensor, 2×16 backlit LCD, BASIC stamp 2 board, and an XBee 2-pack that we assume would be priced above girlfriend approval levels.
We’re curious about how many (and in what quantity) of these items will be stocked at the East Nowheresville strip mall, and again there’s no mention of improving the selection of individual components.
At Hack A Day, we were thinking how amazing a Radio Shack ‘component vending machine’ would be. A modified pick and place machine that will dole out caps, resistors, other components, and has the potential to be competitive with online stores. Anyone feel like sending that suggestion in?