Posts with «kit» label

Build an automatic cat treat dispenser with Hummingbird

The Hummingbird by BirdBrain Technologies is an Arduino AtHeart microcontroller designed to enable beginners to create robots from craft materials. Hummingbird kits include LEDs, motors, and sensors that connect directly to the board. This eliminates the need for soldering or breadboarding and ensures that users have the parts they need to build their first robots. All of the components are reusable, so the same kit can be used to build many different robots.

In addition, the Hummingbird supports a variety of programming options, making it appropriate for beginning programmers as well as those who are more advanced. Some programming languages, such as Scratch and Snap!, can only be used when the board is connected to the computer. We will concentrate here on programming alternatives that enable users to upload a program onto the board’s Arduino.

Classrooms all over the world have used the Hummingbird from elementary to high school for projects ranging from Shakespeare dioramas to the physics of amusement park rides. In the following project, the BirdBrain Technologies team will show how they used the Hummingbird to build an automatic cat treat dispenser and demonstrate how the Hummingbird can be utilized to construct robots from everyday materials.

Building with the Hummingbird
Beginners can easily get started building Hummingbird robots with cardboard and craft materials. Motors, sensors, and LEDs can be connected directly to the Hummingbird board, and these elements can be added to the robot with hot glue. Hot glue peels off the components so that they can later be reused.

The example project uses one servo motor, one single color LED, and a light sensor. The dispenser consists of a servo motor attached to craft sticks that block the bottom of a chute containing cat treats. The position of the servo motor can be changed in software to release treats.

To receive a treat, the cat must cover a light sensor in front of the chute. When the cat covers the sensor, the servo motor briefly moves to open the chute and dispense a treat. The LED was included to show our test cat the location of the light sensor.

Programming with the Hummingbird
One unique feature of the Hummingbird is that it supports three different programming options for producing an Arduino program. These options provide steps of increasing difficulty to support learners as they transition from programming novices to Arduino experts.

Beginners can start with the CREATE Lab Visual Programmer. This software option is based on storyboarding. Users can select the motors and LEDs that they are using on a schematic of the Hummingbird board. Then they can create expressions by using sliders to set the values of these outputs. The expression below sets a servo motor to 100°.

Expressions can be combined to create sequences. For example, the sequence below controls our automatic cat treat dispenser. This sequence is controlled by a sensor block. If the light level is low, the three expressions on the left are executed. If the light level is high, the three expressions on the right are executed. The user can then convert this sequence to an Arduino program by simply clicking the “Export Sequence” button (shown outlined in red). The Hummingbird can then be placed into Arduino mode and the program uploaded to the microcontroller.

Another option for beginners is ArduBlock, which provides a visual introduction to the Arduino language. The Hummingbird extension for ArduBlock includes a block for each Hummingbird component. A program in ArduBlock to control the treat dispenser is shown below. This program is equivalent to the CREATE Lab Visual Programmer sequence shown above.

The Arduino code generated by this ArduBlock program is shown below. Individuals moving from the CREATE Lab Visual Programmer or ArduBlock to Arduino can start by modifying the generated code. For example, in the video we modified the commands inside the else to make the LED blink to attract the cat’s attention.

Once individuals are comfortable with the Arduino programming language, they can create more complex programs in Arduino. For instance, the video shows how we modified our robot and our code to incorporate three lights and three sensors. To get a treat, the cat must cover the sensor when the corresponding light is on.

The cat treat dispenser is only one example of a Hummingbird robot using the power of the Arduino at its core. The parts can be used and reused to construct an unlimited number of robots with low-cost materials such as cardboard, pipe cleaners, recycled materials, and even paper mache!

Add Robotic Farming to Your Backyard with Farmbot Genesis

Growing your own food is a fun hobby and generally as rewarding as people say it is. However, it does have its quirks and it definitely equires quite the time input. That’s why it was so satisfying to watch Farmbot push a weed underground. Take that!

Farmbot is a project that has been going on for a few years now, it was a semifinalist in the Hackaday Prize 2014, and that development time shows in the project documented on their website. The robot can plant, water, analyze, and weed a garden filled with arbitrarily chosen plant life. It’s low power and low maintenance. On top of that, every single bit is documented on their website. It’s really well done and thorough. They are gearing up to sell kits, but if you want it now; just do it yourself.

The bot itself is exactly what you’d expect if you were to pick out the cheapest most accessible way to build a robot: aluminum extrusions, plate metal, and 3D printer parts make up the frame. The brain is a Raspberry Pi hooked to its regular companion, an Arduino. On top of all this is a fairly comprehensive software stack.

The user can lay out the garden graphically. They can get as macro or micro as they’d like about the routines the robot uses. The robot will happily come to life in intervals and manage a garden. They hope that by selling kits they’ll interest a whole slew of hackers who can contribute back to the problem of small scale robotic farming.


Filed under: cnc hacks, green hacks

the easiest educational robot for kids, Mbot, goes AtHeart

It’s cute, it’s fun and easy to assemble, it’s mBot by Makebloc, the new educational robot joining Arduino AtHeart program!

mBot it’s an all-in-one solution for kids and beginners to enjoy the hands-on experience about robotics, programming, and electronics.

You can program it with drag-and-drop graphical programming software based on Scratch 2.0 and the magic happens: the robots can follow lines, kick balls and push objects, avoid walls and more. You can also switch from graphical to text-based programming in Arduino mode as it can be coded with Arduino IDE environment.

Watch the video of their successful Kickstarter campaign:

mBot supports wireless communication, standard Arduino boards like Arduino Uno, Leonardo boards, Arduino Nano, Arduino Mega 2560, Makeblock mCore (based on Arduino Uno).

The main control board’s design, mCore of mBot, is based on Arduino UNO: with intuitional color labels and easy-to-use RJ25 connectors, the board can get wired easily so students can then get more time to focus on creating all kinds of interactive stories and projects.

To help teachers, parents, and kids get started easier and faster the robot kit has two free tutorial e-books and online manuals are provided and increasing continually.

Take a look at mBot on Makeblock website and discover how to use 2.4GHz wireless module and Bluetooth module with mBot:

Arduino Blog 30 Nov 15:15

A DIY smartwatch designed by a kid for kids

Omkar is a special 8 years old who created a wearable device called O Watch: an Arduino Zero-based smartwatch kit for kids. The project, recently kickstarted, allows young people to learn programming, 3D printing and a bit of craft while making their own smartwatch and customizing it. The kit will be released with a series learning tools including a kid-friendly website with easy tutorials, examples and a community to share creations.

He’s not new to DIY tech and learning as he’s been doing a few workshops to teach Arduino to other kids and likes it when they get excited about making Arduino projects. Omkar told us:

I was first interested in robots. But my dad got me started with projects that light up LEDs that were easier to learn and code myself. (ps: my dad did not let me get a robot kit at first :).

I decided to do a wearable project because there were many of them I saw in the news and I thought they were cool. I wanted to make a smartwatch so that I could wear it myself and share my project with my friends in school.

If you are a kid and are new to making, O Watch could be a great starting point as you’ll learn about coding, 3d printing, craft and also sharing. The Arduino IDE will be your  primary programming tool for the watch, the case can be 3D printed in a color of your choice and you’ll experiment on how to knot yourself a cool band to wear it.

What are you waiting for? You have just a few days to back the project on Kickstarter and have an O Watch delivered to your home!

Arduino Blog 08 Sep 23:03

Autodesk teams up with Arduino to electrify creativity and coding

We are excited to introduce our new collaboration with Autodesk, launching with us the Arduino Basic Kit in the US! Starting today we are bringing creativity and electronics to everyone wanting to get started with more than 30 components added into the 123D Circuits simulator and 15 step-by-step tutorials available through the Project Ignite learning platform.

With the Arduino Basic Kit you’ll be able to access digital simulations for a unique experience of engagement with the kit, understanding and tapping right away into the power of smart objects.

“Arduino is creating new opportunities for makers and educators to get hands on with coding and electronics,” said Samir Hanna, vice president and general manager, Consumer and 3D Printing, Autodesk. “Our collaboration with Arduino will enable our passionate community of users to unlock their creativity while building the skills to succeed in a technologically-focused world.”

“By collaborating with Autodesk on the Arduino Basic Kit we are showing that designing electronics is a great educational area for teachers,” said Massimo Banzi, co-founder of Arduino. “By offering our tutorials in digital format instructors can involve students of all ages on interactive projects within Project Ignite platform.”

Autodesk recently launched Project Ignite during the White House National Week of Making to provide a free and open learning platform that builds the skills of young learners through creative, hands-on design experiences focused on the latest technology trends like 3D printing and electronics. Through these efforts, Autodesk aims to empower the next generation of innovators with the tools and confidently enter this new future of making things.

 

What’s in the Arduino Basic Kit:

  • All the physical and digital components you need to build simple projects and learn how to turn an idea into reality using Arduino and Autodesk 123D Circuits.
  • The digital simulations in 123D Circuits provide a unique experience to engage and learn about the power of smart objects .
  • Exclusive online access to 15 step-by-step tutorials, through the Project Ignite learning platform, to make simple projects using components that let you control the physical world.

Projects include:

  • Get to know your tools: An introduction to the concepts you need to know to advance
  • Love-O-Meter to measure how hot-blooded you are
  • Zoetrope to create a mechanical animation you can play forward or reverse
  • Knock Lock to tap a secret code and open the door

Get your kit today, exclusively at www.autodesk.com/arduino for $84.00.

Join the conversation on the Arduino Forum.

 

Solderless Noise-o-Tron Kit Makes Noise at Chicago Makerfaire

Anyone who’s manned a hackerspace booth at an event knows how difficult it can be to describe to people what a hackerspace is. No matter what words you use to describe it, nothing really seems to do it justice. You simply can’t use words to make someone feel that sense of accomplishment and fun that you get when you learn something new and build something that actually works.

[Derek] had this same problem and decided to do something about it. He realized that in order to really share the experience of a hackerspace, he would have to bring a piece of the hackerspace to the people.  That meant getting people to build something simple, but fun. [Derek's] design had to be easy enough for anyone to put together, and inexpensive enough that it can be produced in moderate quantities without breaking the bank.

[Derek] ended up building a simple “optical theremin”. The heart of this simple circuit is an ATTiny45. Arduino libraries have already been ported to this chip, so all [Derek] had to do was write a few simple lines of code and he was up and running. The chip is connected to a photocell so the pitch will vary with the amount of light that reaches the cell. The user can then change the pitch by moving their hand closer or further away, achieving a similar effect to a theremin.

[Derek] designed a simple “pcb” out of acrylic, with laser cut holes for all of the components. If you don’t have access to a laser cutter to cut the acrylic sheets, you could always build your own. The electronic components are placed into the holes and the leads are simply twisted together. This allows even an inexperienced builder to complete the project in just five to ten minutes with no complicated tools. The end result of his hard work was a crowded booth at a lot of happy new makers. All of [Derek's] plans are available on github, and he hopes his project will find use at Makerfaires and hackerspace events all over the world.

 

 

 


Filed under: ATtiny Hacks, Hackerspaces

Project Review – Silicon Chip Capacitance Substitution Box

Introduction

Every month Australian electronics magazine Silicon Chip publishes a variety of projects, and in some cases various (well … one of two) electronics retailers will pick up the project and offer it as a kit. However for an increasing number of new projects they don’t, which leaves the interested reader with one option – build the entire project from scratch.

But thankfully this is no longer the case – as the team from Silicon Chip now offer a range of project PCBs and matching front panels for sale directly from their website. Although buying these parts is not the cheapest option, it gives the busy person who likes making things a quick start – or the inexperienced more opportunities to complete a successful project.

So as a test of this new service, I bought the PCB and front panel for the Capacitance Substitution Box project described by Nicholas Vinen in the Juily 2012 issue of SC:

This is something I’ve meant to make for a while – but didn’t really have the inclination to make one from scratch, so it was neat to see a version published in the magazine. I believe the subjects in the magazine article are oftern prototypes, which explains the difference in colour for the front panel.

The parts arrived in a week after placing the order, and are of a high quality:

When complete, the capacitance substitution box PCB and panel will fit nicely into an Altronics H0151 enclosure, so you don’t need to do any drilling or filing. The next task was to organise the required parts. The rotary switches, terminal posts and the usual odds and ends can be found at Altronics, Jaycar or other suppliers. However the main components – the capacitors – offered two options.

The first option is to simply use capacitors from personal stock or the stores. However the tolerance of these parts can vary wildly, with up to twenty percent either way. This is ok for simple uses, however when values are combined – the tolerance of larger values can negate the lower values completely. So instead I’ve chosen the second option – which involves using brand-name low-tolerance capacitors.

Thus I turned to element14 who stock not only a huge range of not only regular but also the low-tolerance capacitors, and can also have them on my desk usually by the next working day. Finally, it’s nice to have all the parts arrive in little bags… neatly organised ready to go:

It’s easy to search for low-tolerance parts with element14, as the automatic filtering has tolerance as a parameter:

Furthermore you can also ensure you have the voltage rating of at least 50V DC as well. So after half an hour the capacitor order was completed and arrived when expected – using parts from Panasonic, Vishay, and Wima. The tolerances of our capacitors used varied between one and ten percent, which will help improve the accuracy of the substitution box.

Assembly

The PCB has the capacitor values labelled neatly on the silk-screen, so soldering in all the capacitors was a relatively simple but long operation. Having them arrive in separate packets made life a lot easier. During the soldering process it’s a good idea to have a  break or two, which helps you avoid fatigue and making any mistakes.

There may be a few capacitors that are a little too wide to fit with the others, so they can be mounted on the other side of the PCB:

However they all end up fitting well:

The next step was to configure the first rotary switch for six position use, then cut the plastic stopped from the side of each rotary switch. In the following image you have a before and after example:

Now the rotary switches can have their shafts trimmed and then be soldered onto the PCB:

However ensure you have the first rotary switch in the right way – that is the selections are selected across the top half, not the bottom. Remove the nuts from the rotary switches, and double-check all the capacitors are fitted, as once the next step is completed … going back will be difficult to say the least.

At this point the banana sockets can be fitted to the panel, and then soldered into place, and then you’re finished. Just place the panel/PCB combination inside the box and screw it down:

Using the Capacitance Substitution Box

Does it work? Yes – however you don’t get exact values, there will always be a tolerance due to the original tolerance of the capacitors used and the stray capacitance of the wires between the box and the circuit (or capacitance meter). Nevertheless our example was quite successful. You can see the box in action with our Altronics LC meter kit in this video.

Again, using the best tolerance capacitors you can afford will increase the accuracy of this project.

Conclusion

Over time this would be a useful piece of equipment to have – so if your experiments or projects require varying capacitor value, this project will serve the purpose nicely. Plus it helps with mental arithmetic and measures of capacitance! Please do not ask me for copies of the entire Silicon Chip article, refusal may offend. Instead – visit their website for a reprint or digital access.

And if you enjoyed this article, or want to introduce someone else to the interesting world of Arduino – check out my book (now in a third printing!) “Arduino Workshop”.

Have fun and keep checking into tronixstuff.com. Why not follow things on twitterGoogle+, subscribe  for email updates or RSS using the links on the right-hand column, or join our forum – dedicated to the projects and related items on this website. Sign up – it’s free, helpful to each other –  and we can all learn something.

The post Project Review – Silicon Chip Capacitance Substitution Box appeared first on tronixstuff.

Kit Review – Altronics/Silicon Chip ISD2590 Digital Message Recorder

Introduction

Every month Australian electronics magazine Silicon Chip publishes a variety of projects, and in February 1994 they published the “90 Second Digital Message Recorder” project. That was a long time ago, however you can still find the kit today at Altronics (and at the time of writing, on sale for AU$26), and thus the subject of our review.

The kit offers a simple method of recording and playing back 90 seconds of audio, captured with an electret microphone. When mounted in a suitable enclosure it will make a neat way of leaving messages or instructions for others at home.

Assembly

The kit arrives in typical Altronics fashion:

… and includes everything required including IC sockets for the ISD2590 and the audio amplifier:

The PCB missed out on silk-screening – which is a pity:

however it is from an original design from twenty years ago. The solder mask is neat and helps prevent against lazy soldering mistakes:

Finally the detailed instructions including component layout and the handy Altronics reference guide are also included. After checking and ordering the resistors, they were installed first along with the links:

 If you have your own kit, there is a small error in the instructions. The resistor between the 2k2 and the 10uF electrolytic at the top of the board is 10k0 not 2k2. Moving on, these followed by the capacitors and other low-profile components:

The rest of the components went in without any fuss, and frankly it’s a very easy kit to assemble:

 The required power supply is 6V, and a power switch and 4 x AA cell holder is included however were omitted for the review.

How it works

Instead of some fancy microcontrollers, the kit uses an ISD2590P single chip voice recording and playback IC:

It’s a neat part that takes care of most of the required functions including microphone preamp, automatic gain control, and an EEPROM to store the analogue voltage levels that make up the voice sample. The ISD2590 samples audio at 5.3 kHz which isn’t CD quality, but enough for its intended purpose.

Apart from some passive components for power filtering, controls and a speaker amplifier there isn’t much else to say. Download the ISD2590 data sheet (pdf), which is incredibly detailed including some example circuits.

Operation

Once you apply power it’s a simple matter of setting the toggle switch on the PCB down for record, or up for playback. You can record in more than one session, and each session is recorded in order until the memory is full. Then the sounds can be played back without any fuss.

The kit is supplied with the generic 0.25W speaker which is perhaps a little weak for the amplifier circuit in the kit, however by turning down the volume a little the sound is adequate. In this video you can see (and hear) a quick recording and playback session.

Conclusion

This kit could be the base for convenient message system – and much more interesting than just scribbling notes for each other. Or you could built it into a toy and have it play various tunes or speech to amuse children. And for the price it’s great value to experiment with an ISD2590 – just use an IC socket. Or just have some fun  – we did.  Full-sized images are available on flickr

And if you enjoyed this article, or want to introduce someone else to the interesting world of Arduino – check out my book (now in a third printing!) “Arduino Workshop”.

Have fun and keep checking into tronixstuff.com. Why not follow things on twitterGoogle+, subscribe  for email updates or RSS using the links on the right-hand column, or join our forum – dedicated to the projects and related items on this website. Sign up – it’s free, helpful to each other –  and we can all learn something.

The post Kit Review – Altronics/Silicon Chip ISD2590 Digital Message Recorder appeared first on tronixstuff.

Tronixstuff 23 Jan 03:34

Old Kit Review – Talking Electronics Fluorescent Simulator

Introduction

Slowly we’re working through the stock of old kits, and in this article we have the “Fluorescent Lamp” simulator from Talking Electronics. To save repeating myself you can read more about Talking Electronics here and watch interviews of the founder Colin Mitchell here.

So why would you want to simulate a fluoro’ tube anyway? Model railways! When your model world moves from day to night, it’s neat to have street lights and so on “flicker” on just like the real thing. And thus you can create this effect as well. It can drive incandescent lamps up to 12V, and allowing it to be powered easily from most layouts.

The kit was originally described in the Talking Electronics book “Electronics for Model Railways” (volume 1) which was full of useful and interesting electronics to liven up any layout. The book may now out of print however at the time of writing this you can download or view most of the projects from the index column of the Talking Electronics website… or contact Talking Electronics if they have any copies of the book (or kit) to sell.

Assembly

Time was not kind to the kit, to be frank it was surprising to find one at all:

(Just a note for any over-enthusiastic readers, Talking Electronics is no longer at the address on the bag shown above). However it was complete and ready for assembly. The PCB has a silk-screen with the required component placement information, polarities and so on – a first for the time:

The instructions and “how it works” are not included with the kit as you were meant to have the book, however TE have made them available as a separate download (.pdf) The kit included everything required to get started, and there’s an LED which replicates the effect so you can test the board without having to watch the connected bulb (which may be a distance away). Finally an IC socket is included

The actual assembly process was very straight forward, which simply required starting with the low-profile components and working up to the large ones:

The only problem with the PCB was the holes – looks like only one drill size had been used (apart from the mounting holes) which made getting that rectifier diode in a little tricky. Otherwise it was smooth sailing.

Not having a model railway at the moment left me with the simple example of the onboard LED and a small incandescent globe to try with the circuit. You can see the kit working in this video.

John – Why do you publish these “Old Kit Reviews”?

They’re more of  a selfish article, like many electronics enthusiasts I have enjoyed kits for decades – and finding kits from days gone by is a treat. From various feedback some of you are enjoying them, so they will continue for fun and some nostalgia. If you’re not interested, just ignore the posts starting with “Old”!

Conclusion

For a kit from the mid-1980s, this would have solved the problem neatly for model railway enthusiasts. By using two or more of the kits with different capacitor values, many model lights could blink on with seemingly random patterns. However it’s 2014 so you could use a PIC10F200 or ATtiny45 and reduce the board space and increase the blinking potential.

Nevertheless, it was an interesting example of what’s possible with a digital logic IC. Full-sized images and a lot more information about the kit are available on flickr. And if you enjoyed this article, or want to introduce someone else to the interesting world of Arduino – check out my book (now in a third printing!) “Arduino Workshop”.

Have fun and keep checking into tronixstuff.com. Why not follow things on twitterGoogle+, subscribe  for email updates or RSS using the links on the right-hand column, or join our forum – dedicated to the projects and related items on this website. Sign up – it’s free, helpful to each other –  and we can all learn something.

The post Old Kit Review – Talking Electronics Fluorescent Simulator appeared first on tronixstuff.

Old Kit Review – Silicon Chip Transistor Beta Tester

Introduction

After exploring a quiet , dusty electronics store in the depths of suburbia the other week, I came across this kit from Altronics (K2534) which is the subject of this review. The Transistor Beta tester is the second revision of a tester designed by John Clarke for the March 1991 issue of Silicon Chip magazine, and promises to offer a simple way of measuring the gain of almost any NPN or PNP bipolar transistor. But first some public answers to recent feedback…

John – Why do you publish these “Old Kit Reviews”?

They’re more of  a selfish article, like many electronics enthusiasts I’ve enjoyed kits for decades – and finding kits from days gone by is a treat. From various feedback some of you are enjoying them, so I’ll continue with them for fun and some nostalgia. If you’re not interested, just ignore the posts starting with “Old”!

Where’s the schematic?

After publishing a few kit reviews, people have been asking me for the schematics. For kits that are based on magazine articles from Silicon Chip and the like, the details are Copyright and I can’t legitimately give you a copy. You need to contact the magazine or kit supplier. The surviving electronics magazines often run “on the smell of an oily rag” so in order to support them I promote the idea of paying for copies which are obtainable from the magazine. Plus Australia is a small country, where people in this industry know each other through first or second connections – so I don’t want to annoy the wrong people. However Google is an awesome tool,  and if you want to make your own beta tester there are many example circuits to be found – so have fun.

Back to the review – what is “beta”?

Apart from a letter of the Greek alphabet and a totally-underrated form of VCR format, beta is a term used to define the amount of gain of a transistor. From the guide:

Assembly

Here’s our kit from 1991, rescued from the darkness of the store:

Which contained the nice box, plus all the required components except for an IC socket, and a few screws and mounting nuts that should have been included. The instructions looked to be a photocopy of a photocopy, harking back to the 1980s…

Looks like an off-brand 555 has been used (or substituted), however a bit of research indicated that it is most likely from LG Semiconductor:

The PCB was made to the usual standard at the time, just drilled:

The front panel was well done, and kindly pre-drilled by a previous customer. The kit came with a 3mm LED however this mystery person had drilled the hole out for a 5mm:

… but hadn’t cut the oblong for the slide switch wide enough. But the biggest problem was that the PCB was just a smidge too wide for the included enclosure:

Nevertheless it was time to get started, and the resistors were measured, lined up and fitted:

Then the rest of the components fitted as normal, however they need to stay below the horizontal level of the slide switch bezel:

… which was somewhat successful. Then to fit the potentiometer, battery snap …

and the test leads:

 And we’re finished:

How it works

Operation is quite simple, just wire up the test leads to the transistor’s base, collector and emitter – set the PNP/NPN switch and press test. Then you turn the knob until the LED just turns on – at which point the scale indicates the gain.

“Modern-day” replacements

Digital technology has taken over with this regard, and a device such as the one below can not only give the gain, but also the component details, identify legs, and much more:

I’ll be sticking with this one for the time being. Jaycar have discontinued the analyser shown above, but Altronics have the “Peak” unit which looks even more useful.

Conclusion

Well… that was fun. A lot of promise, however with a few details not taken care of the kit was just a bit off. Considering this was around twenty years old and possibly shop-soiled I can’t complain. For the record the good people at Altronics have a great line of kits. Full-sized images and a lot more information about the kit are available on flickr.

And while you’re here – are you interested in Arduino? Check out my new book “Arduino Workshop” from No Starch Press.

In the meanwhile have fun and keep checking into tronixstuff.com. Why not follow things on twitterGoogle+, subscribe  for email updates or RSS using the links on the right-hand column? And join our friendly Google Group – dedicated to the projects and related items on this website. Sign up – it’s free, helpful to each other –  and we can all learn something.

The post Old Kit Review – Silicon Chip Transistor Beta Tester appeared first on tronixstuff.

Tronixstuff 15 Dec 04:15