Getting Ugly, Dead Bugs, and Going to Manhattan

Back in the 1980s I was a budding electronics geek working in a TV repair shop. I spent most of my time lugging TVs to and from customers, but I did get a little bench time in. By then new TVs were entirely solid-state and built on single PC boards, but every once in a while we’d get an old-timer in with a classic hand-wired tube chassis. I recall turning them over, seeing all the caps and resistors soldered between terminal strips bolted to the aluminum chassis and wondering how it could all possibly work. It all looked so chaotic and unkempt compared to the sleek traces and neat machine-inserted components on a spanking new 19″ Zenith with the System 3 chassis. In a word, the old chassis was just – ugly.

Looking back, I probably shouldn’t have been so judgmental. Despite the decades of progress in PCB design and the democratization of board production thanks to KiCad, OSH Park, and the like, it turns out there’s a lot to be said for ugly methods of circuit construction.

Continue reading “Getting Ugly, Dead Bugs, and Going to Manhattan”

VFD 430 Clock, NYC Style

[Daniel] seems to have a lot of time on his hands for building clocks, and that’s fine by us. For his latest build, he used a vacuum fluorescent display (VFD) to display hours, minutes, and seconds using an MSP430 to drive it.

Like the analog meter clock he built recently, there is no RTC. Instead, [Daniel] used the 430’s watchdog timer to generate 1Hz interrupts from the 430’s 32KHz clock. [Daniel] wanted to try Manhattan-style board construction for this project, so he built each module on a punch-cut stripboard island and super glued them to a copper-clad board. We have to agree with [Daniel] that the bare-bones construction is a nice complement to the aesthetic of the VFD.

[Daniel] set out to avoid using a VFD display driver, but each of the segments require +50V. He ran through a couple of drawing board ideas, such as using 17 transistors to drive them all before eventually settling on the MAX6921 VFD driver. The +50V comes from an open-loop boost converter he built that steps up from 12V.

The time is set with two interrupt-triggering buttons that use the shift register example from TI as a jumping off point. All of the code is available on [Daniel]’s site. Stick around after the break for a quick demo of the clock.

Continue reading “VFD 430 Clock, NYC Style”

Printing point-to-point circuits on a 3D printer

[CarryTheWhat] put up an Instructable on his endeavours in printing circuit boards for solder free electronics. He managed to print a flashlight where the only non-printed parts are a pair of batteries and a couple of LEDs.

The circuit is a weird mix of point to point and Manhattan style circuit construction; after modeling a printed plastic plate, [CarryTheWhat] added a few custom component holders to hold LEDs, batteries, and other tiny electronic bits.

To deliver power to each electronic bit, the components are tied off on blue pegs. These pegs are attached to each other by conductive thread much like wirewrap circuit construction.

Right now, the circuits are extremely simple, but they really remind us of a few vintage ham radio rigs. While this method is most likely too complex to print 3D printer electronics (a much desired and elusive goal), it’s very possible to replicate some of the simpler projects we see on Hackaday.

[CarryTheWhat] put the models and files up on GitHub if you’d like to try out a build of your own.

A ham radio receiver, Manhattan Style

If you’ve never heard of “Manhattan Style” circuit construction, you’re not alone. Popular in ham radio circles, the process looks nicer than straight dead bug style circuit building, but not as involved as etching your own PCB – consider it a nice middle of the road solution.

This type of construction is often used to build circuits inside enclosures that are made of copper clad, which is a somewhat common practice among ham radio operators. Manhattan Style circuits are built using glued-on metal pads to which components are mounted. One might think that the large pads you see in the image above would limit you to through-hole components, but that’s definitely not the case. A wide array of SMD pads are available in common pin configurations as well, allowing you to use pretty much any type of component you prefer.

While it might not be appropriate for every project you work on, Manhattan Style circuits and copper clad boxes definitely add a nice touch to certain items, like the Wheatstone Bridge Regenerative Receiver you see above.

[via Make]