Is it an AM radio? Yes. It is a 555 LED flashing circuit? Yep. How about a hex counter with a 7 segment display? That too. Five different colored LED’s to satisfy your need for blinkenlights? Even that! What is this magical contraption? Is it one of those old school 30-in-1 or 50-in-1 “Science Fair” kits with the jumper wires and the springs? Almost!
When [grandalf]’s friend showed them a project where a 555 timer was installed on an Arduino shield, they realized two things: This whole “could have done that with a 555 timer” meme is a lot of fun, and “I’ve got an old 556 chip, I wonder if I can build one?” The answer is yes, and so much more.
Starting with the 556 timer, and inspired by the old spring-and-jumper kits of the past, [grandalf]’s “556 on a Proto Shield” project evolved into a creation they call the Retro Shield. Snowballing like so many hacker projects, it now includes several built in circuits and components. Breadboard jumpers are used to connect components through strategically placed pin headers, of which there are quite a few!
To make it all fit, some parts were substituted with more compact pieces such as an LM386 instead of an LM380. The AM radio portion is supplied by an all-in-one radio chip, the ZN414. With the scope creep picking up steam, [grandalf] eventually added so called sidecars- bits of board that contain controls and a speaker hanging off the side of the Proto Shield.
It is not mentioned if the Retro Shield integrates with the Arduino or not. All the same, the Retro Shield has been used to pick up local AM stations, blink LED’s and amplify audio with the LM386. Like [grandalf] we’re sure that the Retro Shield can be used for much more. We hope that [grandalf] expands on the concept and inspires future hackers to answer the question “I wonder what happens if I try this.”
Back in 2015 [Ben Wang] attempted to re-invent the protoboard with the Perf+. Not long afterward, some improvements (more convenient hole size and better solder mask among others) yielded an updated version which I purchased. It’s an interesting concept and after making my first board with it here are my thoughts on what it does well, what it’s like to use, and what place it might have in a workshop.
The Perf+ is two-sided perfboard with a twist. In the image to the left, each column of individual holes has a bus running alongside. Each hole can selectively connect to its adjacent bus via a solder bridge. These bus traces are independent of each other and run vertically on the side shown, and horizontally on the back.
Each individual hole is therefore isolated by default but can be connected to one, both, or neither of the bus traces on either side of the board. Since these traces run vertically on one side and horizontally on the other, any hole on the board can be connected to any other hole on the board with as few as two solder bridges and without a single jumper wire.
It’s an innovative idea, but is it a reasonable replacement for perfboard or busboard? I found out by using it to assemble a simple prototype.
[Spider!]’s contribution to the pantheon of paintball markers is the SMAC: a unique revision to one of Airgun Design’s ever-popular Automags. We needed our tipster, [Russell] to provide some context on the Automag’s evolution, because the brand has served as a popular hacking platform for nearly 20 years. The most frequent is a “Pneumag” modification, which converts the original, fully-mechanical trigger pull into a version where the trigger actuates a pneumatic cylinder to fire the gun.
According to [Russell], the Pneumag’s trigger must completely release between each shot to properly recharge the firing chamber. Without a full release, the gun can load extra balls into the barrel and lead to gloppy consequences. Electronic controls solve this problem, but [Spider!] favored an analog solution that captured a “less is more” mentality over a pre-fab microcontroller board. He built the circuit around a 556 timer used as a delayed re-trigger, but with a few modifications.
Swing by [Spider!]’s forum post for additional details, a cluster of pictures and a bill of materials. Microcontroller alternatives? We’ve got you covered.
Many of the robots we feature here are driven by some sort of microcontroller, whether it be an Arduino, Launchpad, Picaxe, etc. Rarely do we see a robot however, using analog circuits to perform higher-level functions typically relegated to those more complex controllers. Instructables user [hasn0life] built such a robot recently, which he entered into a contest at his college. After hearing about the 555 design contest from a friend, he tweaked his project and created a wall-following robot using a 556 timer.
The robot is fairly simple when you take a close look, though that does not take away from the elegance of his design. A single IR sensor is used to detect objects in the robot’s periphery, guiding the robot along. When the robot gets too close to a wall, one wheel reverses, pulling the robot away. Once the robot has moved a sufficient distance, the other wheel is reversed in order to straighten out the robot. Then, both wheels work in concert to get the robot moving forward.
Take a look at the video below to watch the robot navigate its way around his workshop, and if you are interested in learning more about analog robotics, check out this post from a few days back.