06 March 2015

Reset Switch

The Logitech Cordless Optical TrackMan trackball that I have is kinda finicky with Mei-chan - every so often, I have to unplug and re-plug the USB cable to get it to work in openSUSE.

I lived with it for quite a while, but when I started thinking about the case for the Pi2 and Banpi, I realized that I won't be able to do such a thing when it happens (I'm planning on using it with the Pi2) since the plug will be inside the case (and there's no way I'm going to remove/secure the lid every time it happens), so I needed some other way to do it. I quickly though of a normally-closed momentary switch that would be on a dongle that would cut the power when I depressed the switch, but I decided that the dongle would be a bit too much of a hassle to make. I then thought of mounting the switch on the receiver itself, but when I looked at it, it didn't seem like there'd be enough space for one.

The next day, I thought of a switch I pulled out of an old UPS, but when I tested it, depressing the button didn't do anything. I figured out that it was a fused switch, which acts like a breaker switch (in layman's terms), so that switch was out of the question. Later that evening, I remembered about the chassis intrusion switches I removed from the cluster nodes and found that it would work quite well despite how deep the button can be depressed (the depress depth to "activate" the switch is quite shallow). I used double-sided foam adhesive to mount the switch to the exterior of the receiver and left it alone for the night. The day after that, I performed the necessary modifications before testing it with Melty.

I have yet to use the button since the modification, but at least it'll be there and be a lot more convenient when it does happen - a quick tap is all it takes!


http://i31.photobucket.com/albums/c365/13x31/ElectroDigital%20Blog/IMG_20150303_181222.jpg~original http://i31.photobucket.com/albums/c365/13x31/ElectroDigital%20Blog/IMG_20150303_181232.jpg~original
The receiver stands on the table like it's oriented here, so the switch is actually on the "side" and not the "bottom"; the wire enters close to the edge of the PCB due to its short length.

Water Cooling / Other Stuff

The article I read is: It's Been A Fun Ride, But I'm Done Water-Cooling My PC (I'm hoping this loads correctly for you, as it didn't load correctly for me on Melty).

I've always thought about doing liquid cooling for a computer, but I've never gotten around to doing it, though I've looked at parts here and here a couple times or so.

One of the things that has kept me away is the fact that I can't find a water block for a Radeon HD 6770 - the thing I would want most to be liquid-cooled. With where I'm working now, I technically could make a custom block, but at some point, I'll probably upgrading the 6770 in Melty to something better, so it'd be a lost cause to make that custom block.

Even though I do want to tinker with liquid-cooling, I don't think I'll ever actually do it for any of my own machines, mainly because of the fact that air-cooling works well enough.

A couple weeks ago, I started working as an electronic assembler for a small company that puts together wheelchairs; besides the obvious PCB work, I also make all the cables.

It's decently interesting and I've learned a bit from it - from SMT to using an oscilloscope. It's been sort of a crash-course though, since the one who was training me was really needed in welding (it also didn't help that some of the parts are really low).

Anyway, I probably won't be posting too much for a couple months or so, since I have a severe lack of money; you'll probably mainly be seeing posts about articles, and maybe some projects/tinkering using parts that I already have.

I've been pondering around with ideas for a case that contains the Pi2, Banpi, and HDD, and so far I've figured out to put it all into a single, pre-made box that I found. Sure it's relatively weather-resistant (weather-proof?), but it was the only box I was able to find that was roomy and rectangular. As far as internal layout, I have yet to figure it out since I have a very vague idea of cable paths for one layout (I'm trying to put the HDD in a place with minimal EMI). In the matter of parts, I'm quite covered, so it's just a matter of getting the parts in that stituation.

Once I'm able to, I'll be setting up the Pi2 and Banpi before I do the first half of wired networking for the second floor. Luckily, there happened to be fishing tape at work, so I can borrow that when I run the Cat6.

I thought there was more I was going to talk about, but I can't remember it - if there was.