I haven't written anything in a long time. Because of changes starting last year I have been away from my tools almost every weekend. Hopefully next year I get the chance to do what I like doing best. Making stuff.
One of the most fun projects was building the photo booth for the Christmas party for work over two years ago. For the party last year I decided to tweak it a little bit by adding a button to turn off/on the flash. But during the party I had to turn the flash on several times because people pressed the button and turned the flash off and other people weren't aware you could turn it back on.
Another tweak was required for my flash diffusser. The flash is really bright so originally I cut a diffusser out of some A4 paper. For normal lightning conditions this works fine and you get the cool effect of a camera flash without ending up squinting in the photos. But the Christmas parties tended to be at a location with very little lighting during the party. So even with the automatic ISO detection a lot of photos looked underexposed. After some hunting around in my flat I found some thin mat plastic that would do the trick. It lets through a lot more light while still diffusing a little.
General build instructions
For the finished photo booth and some build instructions visit my photo booth project page.
It has been a long time since my last post. I had so much many upgrades for my WISP and network that I wanted to do during the Christmas holiday and as usual nothing went as planned. But this is not about that.
This post is about my trial with UNMS. UNMS is Ubiquiti new device management software for WISP. It seems like it is meant to replace AirControl 2 and at some stage integrate with UniFi. Currently the software is in beta with many features missing, According to the roadmap UNMS should be feature complete before 2019. But you can download and install the beta version and have a play around. In my case I acquired an Ubiquiti airCube AC which integrates with UNMS.
Note: AWS might charge you for using their services. Example t2.micro instance is free but t2.small cost me $0.0232 per On Demand Linux Instance Hour.
I followed these instructions: UNMS installation. I started of by creating a free AWS account. Before creating your instance, check if you are in the right region (top right next to you account name). I created an EC2 - t2.micro instance from a template which I then upgraded to a t2.small instance. Associate an IP address with my new instance and update the security groups to unblock port 443 (default port used by UNMS, can be changed).
Navigating to the instance elastic IP-address should bring up the UNMS welcome screen. Once you completed the UNMS basic setup you can set up sites and attempt to connect client devices. I don't want to go into too much detail. The forums are a great resource if you get stuck.
It was an interesting exercise to set this up and learn some basics around AWS. I don't know what I will do in the feature. Probably just install and run it on a home build server instead.
Update: I run UNMS on a local server inside a Virtual Machine. I don't need to run it continuously because I still use AirControl 2 for ease of use with my small WISP. Only when you add newer ubiquiti devices that are not supported by AirControl 2 will you require UNMS.
As you might have noticed I thoroughly enjoy building embedded projects. An Arduino starter kit got me interested in software development and that let me to a bachelors in information technology and my career as a software developer,
Every time when my project has past the initial breadboard prototype phase and I want to create a permanent circuit i hit the same hurdle. I use plenty of IO pins and a lot of the inputs and outputs require either a input voltage or reference to ground or both, Most boards only provide one or two, maybe three of these. So I designed a simple breakout board to solve this issue.
In the photo above the bottom row is where you would connect it to your microprocessor. The next two rows are connected to these pins and provides the ability to add pull/down resistors. If you want to use servo connectors then the next row should be bridged to your VCC pin so you create a VCC rail and the top rail should be bridged to GND to create a reference to ground rail. I attached some photos of a recent project where I used two boards to breakout all the pins for an Arduino pro micro. I also upgraded my raspberry Pi photobooth with one of these breakout boards.
I am very happy with the result. I used EAGLE to design the PBS's and https://oshpark.com/ to manufacture them. oshpark provides a EAGLE plugin that will help generate the files for manufacturing to their liking. And that's a very big help for an amateur digital PCB design like me.
Taking your prototype to complete project has never been so easy. See attached files if you want to make your own.
A while ago I ordered some LED flickering candles. This particular set comes with build in rechargeable batteries and a charging tray. It comes with a European style 7.5v power supply which is no good to me without a travel adapter. Instead I wanted something simple. No adapters, or buying a new power supply. Opening the charging tray revealed a simple circuit containing a 5V regulator. That's convenient. This makes it well suited for charging via an USB cable.
While checking the circuit I discovered the current limiting resistor for the LED to be very large. 1K ohm, while 210 ohm would have been enough in it's original configuration. I think it was done to reduce the brightness of the LED. With my conversion to 5V I swapped out the resistor for a 100 ohm resistor, which results in 20mAh going through the LED. It's now nice and bright.
Because the batteries don't have any markings on them and there is no overcharge protection anywhere It is not recommended to leave them on charge for a very long time. At least I have now a convenient charging solution.
Parts have been trickling in and I found something that will make a decent permanent enclosure. I had the misfortune to receive a partially defective rotary encoder which has been replaced. In the photos below all the connections are made with the appropriate current limiting resistors so I could writing the code for all the buttons and LED animations. A video of it working is still to come. I attempted to digitally design a circuit board and have it manufactured. At the time of typing this the manufacturers website is unavailable so I can not check the status of my order. Hopefully more about that next time.
Back to the controller. So far it consist out of:
Up next is permanently wiring things up and 3d printing a bracket to hold the microprocessor in place. And some tidying up of the code so it will be in a good enough state to publish.
George Timmermans, Research Toolmaker, Software Engineer and Tinkerer