In my life and work I walk the fine line between technology and craft. I am suspicious of the new, but am drawn to it. I grew up on a homestead in remote Alaska and have a Masters degree from ITP, an arts, technology, and engineering program at NYU in New York City. I've been a janitor, and a bicycle mechanic; A CNC programmer, and an electrical engineer. I currently live in Fairbanks, Alaska, where I work and play.
I’ve been working with the University of Alaska Fairbanks to develop several systems to help measure water flows in the boreal forest.
I built a system of Dendrometers last year(public lab documentation), and have started the development process on a new sensor system to measure sap flow and water content in trees.
The sap measurement system is based on a description by Vandegehuchte and Steppe in the paper “Sapflow+, a four-needle heat-pulse sap flow sensor enabling nonempirical sap flux density and water content measurements” and my previous work with compost monitoring systems and dendrometry.
While the sap system is still in the testing and development stage, documentation and design files for both projects are located on the Gitlab project Tree Water Sensors.
It was shipped via DHL, and arrived without incident. It was nicely packaged, no damage etc. It did not include any instructions or documentation however.
The main box was full of bubble wrap
Which inclosed this box
Again, no packing list, no instruction sheet, no documentation, no parts list
Inside that box was a anti-static bag enclosing all of the parts for the kit.
I have a fair amount of circuit assembly experience, so the actual assembly of the kit was not a problem for me. As you can see, the board is well labeled as far as the value and polarity of each component. Knowing how to read resistor color codes is important. I just used my multi-meter to test the resistors. Having resistors that are labeled with their values would make the kit assembly easier. The kit itself doesn’t really NEED documentation IF you have experience, but for folks new to electronics and circuits this would be a serious challenge.
The only parts I found somewhat confusing where the placement of the screen, and the test socket. I had to reference the images on the product page on GearBest to find the proper pin placements for the screen and how it should attach, and how to use the test socket.
The assembly was quick and easy for me and I only had one part left over…which I’ve surmised is for calibration purposes.
This device is labeled as a Transistor tester, but can do much more than that. It tests Capacitance, Resistance, and Transistor types and voltages. It can also work as a function generator, frequency tester, and frequency generator. I have not tested these features yet. It is powered off of a single 9v battery, and does self-diagnostics and calibration. The brain is the common ATMEGA328p, commonly found in the Arduino development board family.
Testing a Green LED
Testing a TIP120
Extra Menu Options
I look forward to using this device to sort my pile of misc. transistors and as a tool to help me to continue not having to remember part codes.
This Transistor Tester is a powerful tool to have access to. It can do a variety of testing and diagnostics and will save you having to look up multiple datasheets for parts. The product would be improved with an assembly guide and a short manual on how to use the different modes and functions but for an experienced hobbiest it will be a breeze.
Thanks GearBest for the opportunity to review this product.
Note: This is a tutorial using the Arduino IDE v1.0.6. Version 1.5 and greater uses a built in board manager for board definitions. Please refer to the Google!
In this tutorial we will be setting up an Atmel ATmega328p microcontroller in a breadboard, configuring it to run at 8mhz using the internal clock, and loading the Arduino Bootloader onto it. We will then talk briefly about Low Power operation and show an easy way to put the microcontroller to sleep at ~ 5 microamps of power consumption.
If you test the current with a multi-meter, you will see a dramatic decrease in power consumption during the time that it’s waiting.
This is a tutorial that retroactively follows the workshop I taught in April 2014 at ITP on building an 8 step sequencer/oscillator. It is designed to fit on a 64 row breadboard with very little room to spare. There are many ways that it can be built, but organization and careful attention is required either way. This tutorial is a mixture of schematics, pictures of how I like to breadboard this circuit, and videos of the tests I performed.
…with navigating a breadboard or don’t know the pin numbers and orientation of an IC package go read the following before continuing.
I am not going to number arbitrary steps, but do not be fooled, this is a sequential process.
This is the breadboard, we are going to fill it.
bridge the power busses first so we have power and ground on both sides.
Install the 555 timer with Pin 1 in Row 2.
This is the Schematic of this portion of the circuit:
The 1k resistor is going from Pin 6 on the 555 to Row 1, and the middle pin of the potentiometer is connected to Row 1 and the other pin is connected to Row 3 (Pin 7). The rest should be self explanitory from the schematic and the image. Once that it put together attach a 1k resistor and an LED to Pin 3 of the 555 (the output) to test and make sure it is working. The LED should blink fast and almost look solid when the pot is turned all the way up, and slow down when the pot is turned the other direction.
Next install the 4017 as close as possible to the 555. There shouldn’t be any open rows between them. On the 4017, Pin 16 goes to VCC (power) and pin 8 goes to Ground which is not reflected in the schematic
Step number 8 (pin 9) is connected to the reset (pin 15). When pin 9 goes HIGH the chip resets to Step 1. It is possible to make the sequence shorter by setting a different step to the reset pin, or make it longer by chaining multiple 4017’s together.
The output of the 555 (Pin 3), which is our master clock is connected to pin 14 of the 4017 (the clock input). 13 is connected to ground and the rest of the pins are either not used or our step outputs. At this point we should be able to attach LED’s to the step output of the 4017 and have them turn on and off in a sequence.
After we have tested that and made sure everything is working lets install the 4093 IC’s.
They should also be as close as possible to the rest of the components. There will be a 1 row gap between the two. From now on I will refer to 4093 #1 as the one that is closest to the 4017 and 4093 #2 as the one that is further away. This is important for getting our oscillators and controls synced correctly. Inside each 4093 are 4 NAND gates (hence the name Quad NAND Gate). We are using as a gatable oscillator. Each NAND gate will be the audio in one step of our sequencer.
On each NAND gate, 1 is the Gate. When it is pulled HIGH the osciallator turns on. When it is pulled LOW it will turn off. 2 is conneceted to ground through a 1uF capacitor. 3 is our audio output. A resistor (in our application it is a Light Dependant Resistor (it will be refered to as an LDR from now on)) bridges 2 and 3 and will control the pitch of our oscillator in this circuit. The 4 NAND gates inside each 4093 are laid out like this:
Pins 1, 6, 9, and 12 are our gate inputs, which will connect to the outputs on the 4017. The pin connections are pretty self explanatory if you ponder it. The pin outputs of the 4017 in order from step 1 to step 8 are as follows: 3,2,4,7 10,1,5,6 :: those will get connected to the gates of the two 4093’s. On the 4017 Pins 3,2,4,7 get connected to 4093 #1 Pins 1,6,9,12 respectively and (on the 4017) Pins 10,1,5,6 get connected to 4093 #2 Pins 1,6,9,12. This should look like this:
4093 #1 is done
4093 #2 is done
Next we attach 1uF capacitors between Pins 2, 5, 8, 13 and ground on each of the 4093’s. It should look like this:
At this point we should be able to test to make sure the oscillators are making sound and gating on and off. Temporarily plug an LDR into Pins 2 and 3 on 4093 #2 and connect Pin 3 to an audio output and listen the result. It should beep at you and if you turn the pot connected to the 555 the rate of those beeps should change.
After that successful test, unplug that LDR and set it aside. We’ll use it later. Next we’re doing to preparation layout for the next steps. on the top half of the breadboard starting from row 63, connect every 4th row to power down to row 34 AND starting on row 60, connect every 4th row to itself in a daisy chain down row 35. Connect Row 35 to Row 30, which should be connected to 10k Resistor connected to Ground. An additional step, which is useful but not pictured, is to connected Row 30 to Row 31 via a little tiny jumper wire. It will give us a little more room to work with later on.
What we are going to do next will make sense later on, but we must do it now. We are taking a wire and connecting Pins 2,5,8,13 of each 4093 (the ones with capacitors attached to them) and connecting them in order to to Rows 32 and then sequentially 4 Rows up for each oscillator. We will number our oscillators in the same way the Pins of the IC’s are numbered (counter clockwise around the chip starting at the lower left). Oscillator #1 is the lower left of 4093 #1, Oscillator #2 is the lower right, Osc. #3 is upper Right, Osc. #4 is upper Left. Osc #5 is 4093#2 lower left, and so-on.
Once those wires are placed we will take Pins 3,4,10,11 of each 4093 and run wires to the empty row directly down (in number) from the yellow wires we just placed. We should do this in sequence as well, with Oscillator #8 being the furthest Right, and oscillator #1 being on the left. We should use a different color here, because these are our Audio Outputs. I chose White. Effectively we are breaking out our LDR pitch control to be in a more useful place (directly across from the big expanse of open board that we are about to fill). We will be placing our LDR’s shortly, but first we need to put in some capacitors for our DC blocking filter.
This is what we are building here. This is the schematic for each step of our sequencer. There is the NAND gate we’ve seen before. On the audio output is a capacitor which we are about to put in attached to a 10k resistor, which is already in place (on Row 30). This is a High Pass Filter. Here is why we need it. We are working with logic chips. They operate in the DC world. 0v is OFF, and in our case 9v is ON. They are binary operators, there is nothing else for them. We get square waves from them pulsating between 0 and 9v. Audio is a bipolar signal, which means it oscillates across the 0v in and out of the negative and positive. When each oscillator turns on, it briefly creates a tone and then the signal is pulled high to 9v. If we just connected all these outputs together without a filter, the output of every other oscillator would interfere with every other oscillator. The filter effectively isolates each oscillator and allows them to act as individual units.
We put the filtering capacitors between the White wire we put down and the Blue daisy chain we laid earlier. (the two Rows should be adjacent all the way down to row 31, directly next to the 10k resistor going to ground, creating the other half of our filter)
Now we can put in the 8 LDR’s and test our oscillators again. The LDR’s are connected to the adjacent White and Yellow wire connected to the 4093’s.
To test the audio this time, plug your audio jack into row 30 or 31 (they should be connected by that tiny jumper we put in earlier). You should get results similar to the video below.
We have now completed the noise making portion of the circuit. Now is a good time to go take a break. Stretch, drink some water, look at something at least 20 ft away for at least 20 seconds. Next we are going to tackle the control portion of it, building dimming LED’s using transistors and cute little blue pots.
We are going to place the transistors next. There are 8 of them and they are also placed every 4 Rows starting on the right side of the board. The first one goes in like this and the rest are the same, offset by 4 Rows. Emitter: Bottom Row 64, Base: Bottom Row 63, Collector: Top Row 63 (there should be a connection to VCC (power) on the same row). Place all 8 in this same configuration and then double check to make sure that they are right and follow the schematic above. Again, the Collector should be connected to Power at the top of the board. Once you’re sure those are right, put in the pots, starting on row 63. Put them as close as you can together, leaving one empty row between each (which should be filled by the emitter of the Transistor). The left pin of the pot should be connected to the Base of the Transistor.
Next take 8 pieces of black wire and connect the right pin of each pot to ground.
Then take those outputs from the 4017. (Remember the order. If you don’t, it counts in order: 3-2-4-7-10-1-5-6) Connect the wiper (center pin) of each pot to each respective step output of the 4017 (furthest left pot is step #1, furthest right is step #8. This is correlate with the placement of your LDR’s).
At this point neatness and organization is key to understand where everything is going and where it is coming from. Notice we used BLUE to connect to the Pot’s. Now we are able to easily differentiate between the two different wires going from the same row at the 4017 to two different places. Also note how we wired and tested the 4093’s before we buried them in wire going other places. Next step. Connect the LED’s. Look at the schematic. They will connect to the emitter of the Transistor (step #8 is Row 64) and ground (conveniently located at the pin of the Pot that is connected to ground). Note that the LED’s are polarized. The long leg is positive and should be connected to the transistor. The short leg is ground. You know where that goes.
You’ll get something that looks like this. PLEASE CHECK YOUR CONNECTIONS AGAIN! Make sure the LED’s are connected correctly! Add power and test. It should look like this:
If you turn the pots all the way down the step will turn off. If you turn them up the LED will light and the step will turn on. The further up you turn the pot, the brighter the LED will get. Now you may have noticed that we have these LED’s that blink in sequence, which we can adjust the brightness of. We also have these oscillators that have these light sensors which control pitch directly across from the aforementioned LED’s. It doesn’t take a very far leap to think, “Oh, if we pointed one at the other we might be able to do something interesting”. Lets try it.
I should iterate and re-iterate this too: YOUR AUDIO OUTPUT IS ON UPPER ROW 30. where the 10k resistor is going to ground. That is where your audio comes out. Connect that to a jack somewhere and you’ll be golden. If all this has worked you should feel like the coolest person in the world and you should buy me a beer. If this doesn’t work, or you’re having trouble with the instructions, or you got frustrated with my typo’s or you have other complaints, please contact me and let me know I forgot to include something in my insanity.
Today we are going to be building a simple synthesizer using a 4093 quand NAND gate integrated circuit as the sound source. This tutorial is related closely to the more complicated workshop I taught making an 8 step sequencer using the same chips as the sound source which is here. So lets get started. If you are unfamiliar with navigating a breadboard or don’t know the pin numbers and orientation of an IC package go read the following before continuing.
You’ll start with a bare breadboard below. I usually work with the lowest row numbers on the left, laid out like so.
You’ll have a pile of parts, It is very helpful if they are put out in an organized manner like so. Stay organized and be intentional about what and why you do things. It helps especially as things get more complicated.
Start by pairing the power and ground busses.
And then we will set up some wiring for the audio jack. We’re using a coloring convention that I am a fan of here. We’re making our audio signals yellow, our control signals white, and power and ground red and black respectively. Again, staying organized, it makes everything easier. We’re working with an mono signal so we are going to pair the two channels of the stereo jack (yellow wire from row 1 to 5), we’re also making row 6 (on to the top AND bottom of the board) our audio bus.
Next plug in the audio jack, the center pin going to ground (row 3), and the other two pins plugging into row 1 and 5.
Then we add the 4093. Pin 1 goes into row 7 and is laid out like below. Also attach the power and ground. Power to pin 14, ground to pin 7, just like most of our CMOS logic chips.
Next we add our four switches, starting on row 30 and working our way back with one row separating each switch (like the picture). These switches are connected internally so that the two left pins are connected together and the two right pins are connected together. This bridges the rows across the center channel, which makes some things easier in the future.
We connect the right pins of the switches to power, and the left pins to ground through a 10k-OHM resistor.
These switches will be connected to the gate inputs of the 4093. Pins 1, 6, 9, and 12.
Connect the left side of the switches (the side that is connected to the 10k resistor to ground). Make these connections with white wire, signifying that these are control signals. Switch 1 (farthest left) to pin 1 on the 4093, and switch 2 to pin 6.
Then connect switch 3 to pin 9, and switch 4 to pin 12 like shown below.
Now we will begin connecting the oscillators. There is a schematic showing how each individual one is put together. This synth is simply four of these with their outputs connected together.
Add the capacitors. We’re using 1uF cap in this example, but if you increase the capacitance the frequency of the individual oscillator will drop. Experiment. The capacitors are attached between pins 2, 5, 8, and 13 and ground, respectively.
Now we add the variable resistors, which will give use pitch modulation. They are LDR’s or Light Dependent Resistors. Their name describes what they do. They are connected between pins 2 and 3, 5 and 4, 8 and 10, 13, and 11.
Now all of our oscillators are connected and operational, but we need add a DC blocking filter to each oscillator bring the pulsating DC signal that they are producing to a workable audio signal. This begins with a 10k resistor connected between our audio bus (row 6) and ground.
Then we add a 1uF cap between each audio output (rows 3, 4, 10, and 11) and the audio bus.
Connect the battery (making sure the polarity is right) and press the button. You won’t hear anything unless you’ve connected headphones or a speaker to the headphone jack. Be careful, it’s loud. (+- 4.5 volts)
If you’re having trouble getting this to work, double check all your connections. If that doesn’t work. Tear it all out and start over again.
I operated a small business crafting earrings, belt buckles, and other accessories for a time in 2013. It’s name was Smithcraft Designs, and I used scrap parts of the bike shop I was working in. Stainless steel spokes, and worn chains and other drive-train components to make the items.
I’ve done a wide variety of electronics fabrication in my projects. It all started with the book Handmade Electronic Music and morphed into an interest in music synthesis and music technology, specifically analog synthesis hardware and techniques. I took inspiration from Peter Blasser and built a semi-modular analog synthesiser using his paper circuit fabrication techniques.
I also have worked with high powered LED lighting for bicycles. Using a dynamo hub as a power source, and designed and built stand alone lighting systems (headlight and taillight) and also did LED retrofits on vintage Luxor taillights so they could work with modern headlight systems. During my masters degree, I had access to more advanced circuit design and fabrication tools and learned how to make my own PCBs and about surface mount design and assembly.
This device was built for a USGS study on migrating birds in the boreal-arctic transistion zone in northern Alaska, an area projected to experience more pronounced climate related changes than most other regions. Populations of these migrating birds act as an indicator to monitor changes in climate and habitat.
This data logger records an audio survey of bird songs and weather data during the 3 month field season for later analysis, recording different populations of bird species as they arrive and leave the area.
Arctic and boreal ecosystems provide important breeding habitat for more than half of North America’s migratory birds as well as many resident species. Northern landscapes are projected to experience more pronounced climate-related changes in habitat than most other regions. These changes include increases in shrub growth, conversion of tundra to forest, alteration of wetlands, shifts in species’ composition, and changes in the frequency and scale of fires and insect outbreaks. Changing habitat conditions, in turn, may have significant effects on the distribution and abundance of wildlife in these critical northern ecosystems. - source
The USGS is developing a community-level understanding of ecosystem changes, and with its focus on the Boreal-Arctic transition zone, the work will elucidate wildlife-ecosystem relationships that could help forecast responses in regions farther north and farther south, as factors such as climate warming progress. The initial emphasis is on landbirds and shorebirds. These birds are useful indicators because they are widely distributed, samples are collected by similar methods, and they occupy a wide variety of habitats including wetlands, forests, and shrublands. Using this broad approach will help us understand the “what” and focus attention on the various “why” factors central to the Changing Arctic Ecosystem initiative. Projects in the Boreal-Arctic transition zone are (1) assessing existing population changes, (2) evaluating ecological drivers of population change, and (3) developing scenarios of future abundance and distribution within the boreal and Arctic coastal plain systems. - source
My friend and UAF Masters student, Molly McDermott, worked with one a USGS crew who were handling part of this study. An aspect of their data collection included setting up autonomous audio recording devices to record birdsongs of different species as they moved through the area. The audio was analyzed later in the lab and the data of different bird species, location, and time was inputed into a database.
The study is taking place on the Seward Peninsula within a couple hundred miles of Nome.
What I built was a redesign of the large and expensive data loggers the scientists currently use. It was solar powered, weighed less than 2 pounds (not including a mounting system), and the costs were less than $200. It was made with a customized digital voice recorder, a lavalier mic, and an array of sensors. This version had barometric pressure, humidity, temperature, and was capable of detecting wind speed and wind direction as well. All scheduling and weather data logging was done with an Arduino microcontroller.
Hardware: - Arduino - BMP180 Sensor - EEPROM - Digital Compass Fabrication: - 3d printer - Roland Modela - Manual Lathe Software: - Embedded C - EagleCAD
In 2013 I was working in a bike shop with two talented frame builders, Corey Thompson and Bill Stevenson. They inspired me to begin learning to braze and during the winter of 2013 I built my first frame. I designed the custom frame geometry and built the frame using hand tools and traditional techinques with hand files and brass brazing using and oxy-acetelyne torch. The tubes are fillet brazed together with no lugs. Below is a selection of the photos from the construction process.
The Kinesthete is a new electronic musical instrument that allows for musically intuitively and expressive playability and provides the tactile response and feedback of an analog instrument. The Kinesthete’s controls are not quantized, but are continuously variable inputs evocative of a cello. Discrete musical notes are defined only via physical interaction with the instrument’s fretboard, which allows for a natural expressiveness that is not possible with most digital music controllers or keyboard type instruments.
The Kinesthete generates sound via a real-time synthesis engine running on an embedded ARM processor inside of the instrument. The Kinesthete also has two 15 watt audio drivers in ported enclosures making playable free of external amps or mixers and is capable of creating a stereo sound field and is loud enough to hold its own in a crowded space.
Hardware: - Raspberry Pi - Arduino - Beaglebone xM - Sattelite CCRMA - Teensy3.1 Technology: - ARM Cortex M4 - Atmel GCC toolchain - PWM LED driver - EEPROM Fabrication: - CNC Router - 3d printer - Manual Lathe Software: - Pure Data - Embedded C - Custom Serial Communication Protocols - Solidworks - HSMworks - Illustrator
Compost Sensor is an open source framework for remote environmental sensing. In this application, it is a monitoring tool for small scale urban composting operations.
Hardware: - Arduino - Atmel328 - Adafruit FONA - RFM69 Radio - SHT21 Sensor Technology: - Atmel GCC - 433Mhz Radio - GSM M2M * Fabrication: *- Othermill - 3d printer - Roland Modela - Manual Lathe Software: - Embedded C - EagleCAD - OmniGraffle - Phant - D3.js