I am calling this project DONE for now although I will add more features someday such as an Intercom and SIP phone.
This project required a fair amount of obtanium, tradium and about $350 in cash. It also had some steps where my fingers and body were at great risk so do use caution when using power tools and remember flesh is easy to remove with such devices but very hard to put back.
I based this project around an LCD display and frame used by a salvaged Tektronix scope.
I then used the side panel from an old tower case made with good sturdy steel for the materials for the box I would construct to hold the brains and the LCD module.
The brain is a Single Board Computer a friend is selling. PCI-6881FG. I was concerned about this specialized board failing down the road and not being easy to replace so I also took the time to add mounting holes in the steel for a Mini-ITX board giving myself an upgrade path.
I had to purchase an LVD cables to connect the LCD to the PC from a company here in the US for around $50. I may have been able to make this cable if I could find the connectors but not as well as they did so it was worth the extra money.
I ended up using Kubuntu 11.10 with its newer 3.1 Linux kernel. Oddly enough I had problems with older Linux 2.6 kernels ( wow did I just call 2.6 older ). The new 3.1 Linux kernel worked perfect on this board but I still wish I knew why I had issues with 2.6 based Kubuntu but I do not have the time to find out right now too many projects as it is so I may never know.
To make the frame I used an inexpensive metal bender I acquired for a previous project from Harbor Freight for around $40. I also used a diamond tile saw I had purchased 6 years ago from Home Depot for my kitchen remodel when I did my own granite counter tops with some help from a friend. It is a very noisy way to cut metal but unless you have a press break or know someone who does this IMHO is an excellent and safe way to cleanly cut metal.
I used a rivet gun an inexpensive item most people will have or can get for < $15 to connect the individual metal pieces and form my box.
I then began the dangerous and tiresome task of drilling, cutting and filing out mounting holes for fans PCB mounts fan power etc. This was the most dangerous part IMHO. The wet saw was scary but because the blade is not toothed it is not too dangerous. Your biggest danger with that part is a kick where the blade grabs the metal and turns it into a projectile, Not COOL. Drilling and cutting however are more dangerous because drill bits and sheet steel easily turn into flying spinning sharp metal if one is not very cautious.
I then used some good old fashioned elbow grease and sand paper to clean it all up and then finally paint it with textured durable grade spray paint to give it a powder coat look. I could have had it powder coated here in town but it would have been about $75 and although very cool I could not see the value in it.
Final assembly took place over a few weeks as I had time working out the heat issues. I ended up needing different fans than I had planned on because of cooling issues and noise. I replaced the CPU fan with a super quiet one I purchased from Fry's for $10 and a SUNON HA40201V4-D000 for the case fan. The initial cooling fans I used were noisy and the system was running way to hot about 60c on a good day. I am so far very impressed with the SUNON it has excellent airflow and only a slight whining sound if you listen close and my temp is down to around 40c. We will see how it handles the heat and time the top killers of fans.
The wall where the unit was to be installed was a project in itself. After my kitchen project a few years aback I get razzed a bit for making holes in the wall and this project was no different. I wish I had X-Ray vision or that stud sensors were more accurate because you just never know what you will find till you remove the sheet rock.
I had thought the box would have fit between the studs around the door and the next stud over. As it turns out (I should have known this after the house flip I did a few years back) that several studs stacked together are used to frame in the door. After a few false starts I found a place where I could begin my work and carved out a hole in the sheet rock larger than my final box. I made a wood box out of 1/2” x 4” lumber built the box into my hole.
In my area low voltage work in a conduit does not require a permit according to the folks down at City Hall. So I then ran a 15' section of riser guard down the wall through a hole I drilled under the house into the core of the wall and then into my home automation central computer cabinet. This is never a fun part of this type of project. Anytime you have to crawl around under your house with the bugs dust dirt etc is never fun. Yet another good reason to use conduit.
I then had to find a small amount of 1/4” sheet rock. This was an adventure and I ended up buying a full sheet but only taking home what I needed for the project as my vehicle is not an SUV. I lined the hole with the 1/4” sheet rock and used metal finishing edges for durability. After joint compound sanding adding orange peel and painting I now have a mounting spot for my new Wall PC.
Once the hole I made was all cleaned up I pulled through my 12v DC and cat 6 Ethernet wire from my central DC based home automation core. I added a fuse for that new power line, crimped on an Ethernet plug to one end of the Ethernet wire, and punched down the other end to my network management area of my system.
The final touch was a quick trip to the home improvement store and some nice trim molding. I cut this with a hand held miter saw and built my own picture frame to hide the edge of the case and the transition to the wall.
I had been thinking about how to get video in my AlarmDecoder GUI for a long time in preparation for this project and had a few ideas on how to make it work. Unfortunately most were dead ends. Initially I wanted use HTML5 and its native video support and the ability to access web based home automation systems inside of the AlarmDecoder GUI. I had planned and succeeded in making an HTML5 plugin for the GUI but I found out that no plans for support exist in HTML5 for a video stream that has no EOF such as a webcam. In the end I made a Linux only plugin that embeds mplayer into a window. The plugin spawns two instances of mplayer that are instructed to send video to an X11 window handle I create inside of the TAB on the AlarmDecoder GUI.
I then use mjpg_streamer mjpg_streamer to transmit my video cameras around the house using mjpg protocol.
Some future ideas
- SIP Phone
- Intercom
- Modify the plugin to auto switch back to Video TAB after a timeout so someone using the keypad does not have to worry about it.
- Add some custom graphics to my own AlarmDecoder GUI setup.
- HTML5 plugin to access my home automation system.
Happy Hacking.
Sean Mathews