I wonder if you could get HV/HF enough to skin effect on the moisture in the bread. It would be super dangerous but also fun. I’ll watch from a few feet away @artg_dms
Pencil lead is conductive. Pencil lead is graphite, which is just carbon. Burned toast is carbon.
Minion shaped circuits?
You may be onto something there…
Use a laser to “print” the circuit…
After 75 microcontroller classes, I’m largely dumping breadboards. When I found how easy it is to develop and have printed circuit boards fabricated for under a dollar each, I’m redesigning the future classes and students will plug components into headers. I’ll still teach breadboards and encourage beginners to do a couple of experiments with breadboards. In previous classes, a lot of time was spent with beginners struggling with breadboards. This change will allow me to cover more instructive material and will be less stressful on beginners.
Students would typically wire up a component to an Arduino Nano or RPi Pico W, run an experiment and remove wires before moving on. The left side of the image below shows what it would like to wire up six components at the same time. On the right, an RPi Pico W and twelve components are shown with provision for others. Can you spot all twelve? I just received some of the boards I’ll be using in class. They have provision for four additional components.
I will post this updated version of my Raspberry Pi Pico W: Controlling Sensors with MicroPython in a couple of weeks and a class on designing printed circuit boards a week or so later.
To have a bit of fun, reply with the components you recognize on or attached to the ALEXANDER board. The person that finds the 12th component, not counting the Pico, gets a free pcb. All others can have one for a dollar. Don’t repeat those that have been reported. I’ll check in occasionally to acknowledge correct replies and point out errors. My former students may have an advantage since I think all parts have been used in at lease one class.
Good idea and kudos for still covering breadboards as that is the low barrier entry for a beginner.
Honestly, that pic looks a lot like those infomercials that try to sell you the New Improved Thing by showing you the worst way to do the Old Thing. If that’s the method your students were breadboarding with, no wonder they had issues.
The New Thing does look great, though.
Answers to above challenge to find twelve components:
1 A small trimmer pot with a green dot is the lowest part.
2 Above that is a 0.96" OLED display showing a hammer
3-4 To the right of the OLED are two DS18B20 temperature modules. They use one-wire protocol and the board actually has a header for a third sensor below the other two.
5 Close by and to the right of the higher DS18B20 is an RGB LED module.
6 The lowest connection on the right edge is a WS2612B strip of 42 individually programmable LEDs. The strip goes up and around the LCD display and off to the right.
7 Up a bit is a three wire connection going to the servo in the upper right.
8 The next is four wires going to the 20x4 LCD display with an i2C module. This lets students work with four connections instead of eight plus a resistor without the I2C. This has been a challenge and I still do not have it working with the Pico.
9 The blue box is a DHT11 temperature/humidity sensor.
10 Back-to-back with the DHT11 is a light sensor module. You can see just the edge of the sensor peeking over the board. You have probably noticed that I don’t use the minimal sensors with resistors. Beginners need simplicity of the little modules. If someone wants an LED and resistor, I will explain how to use the red pin and ground of the RGB module. No more tiny wires to get bent up with the breadboard.
11 Past the light sensor is the classic sonic “distance” sensor with transisducers that look like Micket Mouse ears.
12 Along the far edge of the board is a short strip of WS2812B LEDs.
The hole in the low right corner is for a rotary encoder.
Somehow, I knew that @Bill and the other ole timers would be glad that I did not dump breadboards totally.
I have received boards that I will be using in class in a couple of weeks. They have provision for a BME280 type temperature/humidity/pressure sensor, time of flight distance sensor, MPU6050 acceleration/gyro sensor, IR transmitter module, IR receiver module. Also added multiple nodes for +5, +3.3, ground and the only two unused GPIO pins. With all that, I had not filled the board, so I added a 15x5 array of through hole nodes in the lower right. A friend calls it a kludge array. I call it my contingency plan.
All this and you can get five 100x100mm boards from China for $3.50 including shipping. Of course, I plan to have a class to show how easy it is for you to do the same and more. The class will cover from schematic entry, design rule checking, parts placement, auto-routing, and ends with entering your address and credit card info if you want to order your creation. The circuit will be the classic bistable 555 with two LEDs.
I’ve quit breadboarding entire designs. Way too messy to do anything complex. I’ll quickly prototype sub-circuits on a breadboard and once I’ve validated them I’ll lift and shift into my schematic. Once they’re all done I’ll order populated boards. It’s honestly faster, easier and dirt cheap.
I’ll include test pads or untented vias in case I have to blue wire but knock on wood haven’t had any issues that required it.
It is not that I am wedded to wireless breadboards. The serious hardware builders at the 6502 forum almost universally condemn them, especially the cheap imported ones. But they are also pushing and overclocking their processors. Twin Industries is a brand they recommend if you use them.
My point is that designing and ordering a printed circuit board is not good for a beginner or for experimenting with a new concept. Those fancy Pamplin boards are good for reducing distractions during classes. Do you sell them to your students who may want to continue working on their projects?
I wondered how to do that and especially how to deliver them if people not in class wanted them. I’ll probably have some and students can buy them for a dollar. Otherwise, I will share the link and they can order five boards for $3.50 including shipping. They will have the “source code” in the EasyEDA design software so they can modify it as desired.
While to me this is a “gee whiz” project, it really is not. Within the last few weeks, I learned EasyEDA, designed a board for some of my class components and had it fabricated. Then I added more and had boards made,… for times. From EasyEDA, you can choose fabricate and it links you to JLCPCB.
Within a few weeks, I will finalize my design and generate an informal document which includes links to components I buy on Aliexpress. I’ll make the sample programs I use in class available. If anyone wants to order boards and components and sell kits, they could turn a few bucks and be a real service to makers
If anyone wants the board to include connection to other components than I listed above, let me know and I will see what I can do.
If anyone wants to improve my design and post it, that would be great. I’m having fun and want to spread the word. I hope to have a class ready in a few weeks.
I’m not a pro at this. My favorite command is AutoRoute. I cannot even spell Besk Prakitcez.
I love and use EasyEDA for everything. If there was one thing I’d love to see on the board, it would be one or two “MikroBUS” sockets. This would allow the easy use of any of the 1100+ “Click” boards from MikroE. These are breakout boards for all kinds of sensors, communication modules and more. Many/most available from Mouser and Digikey.
I’d be happy to make that addition over the holiday break.
I had not heard of MiccroBUS but, that sounds like a great idea. I’ll PM my contact info.
As I started, I had the luxury of each GPIO pin went to a single component. As it grew and grew, I’m using pins for multiple components. It will be easy to unplug components that are not in use but, I. will need to document which components cannot be used at the same time.
My goal is to get things in order and release my plans just once. Others can take it from there.
Update: My December 7 class just hit the calendar.
https://calendar.dallasmakerspace.org/events/view/20848
Another alternative to the Click boards are Pmods, implemented using a 1x6 or 2x6, 0.1", female right angle header. Initially created by Digilent primarily for Xilinx eval boards, Pmods proliferated everywhere. Pmods, IMO, seems to be a more popular module interface (at least in the US) than Click, which is understandable give where Pmods and Click originated.
Pmods are available in two configurations.
- single, 1x6 with power, gnd, and 4 I/O pins
- dual, 2x6, where the 2nd row replicates the power & ground pins but adds 4 additional I/O, for a total of 8 I/O for the dual interface.
Pmods are nice because they have a small footprint. The Pmod female connectors can also be used as x4 or x8 I/O, with no constraint that a Pmod module be plugged into them.
Digilent offers a really good selection of Pmods - I counted 92 + 2 LabView-specific modules. Not quite the same as 1100+ for click.
Pricing is comparable, based upon a spot comparison for an RS232 board with DB9. Click = $15, Pmod = $14.99.
https://www.digikey.com/en/products/detail/mikroelektronika/MIKROE-1582/4976465
It’s nice to have multiple peripheral module options.
Yet another good idea and a standard that I was not familiar with. I did use a much cheaper RS232 converter on a Richardson Wireless Club high altitude balloon Arduino Nano based project.
I see you snagged a seat in my Dec 7 class. I will look forward to discussing it then.
This idea was moving along with me doing the work and throwing out a board, some documentation and some programs that I use in class.
Above, we have comments from folks that are way ahead of me in this subject area. Would there be interest in meeting together, hammering out the connections to be included, sharing the workload and releasing a nice Dallas Makerspace open source development board?
Yeah until Mouser and Digikey picked them up, there was no real distribution in the U.S. Even now those are the only real sources I’m aware of.
It’s notable, though, that ST has begun including mikroBUS sockets on some of their development/discovery boards.
I wasn’t familiar with Pmods and they look cool, though I did suspect and just confirmed that Pmods must plug into the correct “interface type.” Since they’re constrained by a low pin count, sockets can support only one of SPI, I2C or serial.
In contrast, mikroBUS sockets support all three (assuming the uC does) and any “Click Board” can plug into any mikroBUS socket. Obviously if a uC only has one port of a given type but is connected to multiple microBUS sockets, those sockets will share that port. Generally only a problem with serial since I2C is addressable and SPI has CS.
I’m in for meeting to discuss an open source DMS effort.
With regard to open source boards, it seems that KiCad has supplanted Eagle as the dominate design tool. I’ve hooked my schematic/pcb layout wagon to the KiCad horse. Unfortunately, my wagon hasn’t moved very far 
Interestingly (for me), I found this tool to convert EasyEDA to KiCad. Might be interesting to try it with your current design. Conversion tools can sometimes (usually?) product ugly output.
I’m moving in the KiCad direction because it’s fully open source, while EasyEDA is proprietary (although free for hobby use). One of the EasyEDA attractions is that it’s cloud-based, so instant start with no install/upgrade hassles. However, one never know when the benevolence may decline (see Fusion 360 recent history).