Posts created by “John Miller”

ADS-B and PiAware

I have run some form of an RTL-SDR based ADS-B receiver every since I first learned it was possible back in college. The idea of using a cheap ($10-20) USB radio to pick up aircraft transponder signals, and then use some open source software to decode and visualize it was beyond cool. A few years ago flightware came out with a program called "PiAware" where if you used their software (a combination of raspbian and dump1090 plus some of their own customizations) you could feed your data into their system to help augment their data, and in the process you got a free premium account.

I never used this because 1) I wasn't interested in a premium account, and 2) I ran my own customized version of dump1090 and didn't want to lose out on my sweet added features. Additionally, even though I know that the software can be run on any linux system, I had always felt that the Raspberry Pi was under-powered and not stable enough to run like this for an extended period of time. About a week ago, I decided to revisit the matter, mostly because of the premium account.

I've been doing a lot of testing with my company's real time & big data spatial processing tool, GeoEvent Server and I was under the impression that the premium account would give me an API key to access their feed. Turns out I was wrong, that has to be paid for separately regardless, but I decided to follow through with setting up PiAware anyway. I have an Raspberry Pi B 3 floating around doing nothing in particular, and I figured it should be beefy enough to handle the task at hand.

(picture of setup here)

My setup is simple but works well, it has been running for just a few days now. My number one question, as it always is with deployed RPis, is how well the SD card will hold up. I'm using a 32GB SanDisk Class 1 card, but you never know. My antenna is the official FlightAware branded ADS-B antenna, a dark green plastic tube about 2ft long with an N-connector on the bottom. I have it mounted on top of a tripod standing up in the attic. 20ft of low-loss coax connect it to the receiver - first to a band pass filter that kicks out FM and all the other RF noise, then to the FlightAware Pro radio itself - this is a standard RTL-SDR with a tuner and amplifier somehow "tuned" to 1090MHz. There is a "Pro Plus" version of this receiver now that has the band pass filter integrated, and I would very much like to see how it compares. The last piece is the Pi itself, the only other thing connected to it is a CanaKit 2.5amp PSU - it's hanging off the network via WiFi, also a test.

Performance has been good, the software barely taxes the resources of the machine, and it hasn't had any issues holding up to the network. Their updated version of dump1090 has a number of features that I had added to my own, so I have no qualms with using it now. It also still has the always-updated JSON endpoint with aircraft information which can be readily ingested into GeoEvent Server - more on that later!

Despite being mounted in an attic, surrounded by trees, the coverage is quite good. I find that 7am-1pm tends to be the busiest time.

Re-Fitting the 1050Ti for the TS140

When I first configured the TS140 as my new desktop, I ran into an issue that I pretty much immediately ignored - caused by the 1050Ti's fan shroud. The front panel USB3.0 header and fifth SATA port were completely blocked. Not a "tight fit" situation, but absolutely blocked. My solution was to simply not have front panel USB or a fifth USB port, but that got old quick. Turns out easily accessible USB ports are added to the fronts of many cases for a reason, who would have guessed. Also, I eventually decided I needed to use the optical drive, and the only spare SATA connection was the one blocked by the card, so I had no choice.

My initial solution was to just hack that corner of the shroud off with a dremel and side cutters, but I stopped that line of thought before it got much further than that. Not only would it permanently disfigure the card (making it much harder to sell should I chose to) but I didn't know for sure that the actual heatsink wasn't also playing a role in blocking those parts of the motherboard. The hope was that the fans would be attached to the heatsink somehow so that I could pull off the shroud around them. When I removed the four 1.5mm hex screws holding it down, I learned that I was 1/3 right - in that one each of the three screws holding the fans in place screw into the heatsink.

I pulled off the shroud and removed all six screws keeping the fans in place (not noticing that while the screws are the same length and diameter, those that go into the plastic of the shroud have a much coarser thread than those that go into the metal of the heatsink, causing quite a bit of confusion.)

Once the shroud was off, the hardest part was getting the fans out of it without damaging anything - the wires between the fans, the shroud itself, or most importantly - the blades. It took and incredible amount of finessing and wiggling in order to get them in place. As far as I can tell the manufacturers must either solder the fan wires in after placing the fans, or they have a lot more trust in the flexibility of the blades than I do.

The fans do only attach to the heatsink with one screw each, but they hold in place just fine and don't pivot or hang from that screw due to how they're held in place, and the fact that they don't weigh very much at all. I know it's not an optimal arrangement, but honestly it works just fine as far as I can tell - the GPU gets no hotter than it did before under load. I know some people will probably complain that by removing the shroud I have upset the thermal profile that this was engineered for, and I probably have, but keep in mind that this card is running at less than 75w anyway and I have had cards that pull twice as much power with similar, or worse, cooling configurations.

What really matters is that I can get to the FP-USB3 header and SATA3 unobstructed now. The cable for the USB ports is quite heavy and, if pushed just right, could bump up against that fan, either stalling it or rubbing. I was able to tuck the cable down and it seems to be holding in place just fine, and I can always add a zip tie if need be.

The card looks very naked now, but I can get to the connectors I need and it can still cool effectively. Positioned directly beneath it is a slot powered m.2-SATA adapter. If the m.2 drive in it were a real NVME card it could boot from that slot as well, but it's not so I use a short SATA lead, which works just fine.

Maine: Day 1

I'm actually writing this on day 2 because I didn't have a great opportunity to sit down a write yesterday - or maybe I just didn't want to. Yesterday was great though - the previous day we flew into Portland and after re-exploring the city a bit, we picked up our car (an absolutely ridiculous Infinity Q60 coupe - yay points!) and drove up to the L.L. Bean store to complete the pilgrimage. While we didn't end up getting anything I did decide that I will (eventually) pick up a Hacylon Piranta knife - it's a normal looking folding pocket knife, but instead of a typical fixed blade it uses detachable/replaceable scalpel blades which are both super cheap and sharp. After that we drove back down to North Portland to meet up with some family, my grandfather's brother and his wife. We spent the rest of that evening chatting and catching up, then the following morning we went to the excellent Portland Pottery for breakfast and coffee.

A bit before noon we decided to head off, but not before one more quick stop in North Portland. Something I had been meaning to get Liz quite a while ago was a 35mm lens for her camera, a D3100. She had never shot with a fixed-focal length on a dSLR before, so I figured this would be a great first step - and not very costly either. I actually owned this lens years ago, when the DX version first came out, which I used on my sister's old D50... but I foolishly sold it. Doh. Anyway, the camera shop we ended up (the Photo Market) was fantastic - great guys there, and tons of used gear. Aside from old macs, secondhand camera gear is my favorite type of secondhand stuff.

They had Liz' lens (on sale, no less, ended up getting a new one) and after asking about a used D40 (they didn't have one, unfortunately) I ended up getting my hands on a D80. It actually started with a D70, then a D70s, then finally the D80. I can hear Cory yelling at me now, something about spending money on old gen digital cameras. (Cory, if it makes you feel any better, I'll be loading all of the pictures from it onto a MacPro3,1 running ElCap. :D ) So, yeah, maybe spending money on a 10 year old dSLR wasn't the "best" idea, but 1) it was a good deal, 2) it included a free brand new battery and SD card and a good lens (granted just a kit 18-70, but it's in great shape), 3) the body is in good shape and has a low shutter count.

On from the camera store we drove north on Rt 1 up to Camden. About an hour up, just past Bath, we stopped for lunch at what turned out to be an excellent touristy lobster place (though neither of us had lobster) with an enormous inflatable lobster on the roof - which may have been the only reason we stopped there in the first place. After that it was only about another 30 minutes to Camden, which is just south of our AirB&B. Camden is where we stayed last year, so we re-explored a lot of places we had been before (parks, shops, waterfront stuff, etc.) then drove on north to Lincolnville, just about 10 minutes away.

The place we're staying is right on the coast, and getting down to the water is just a short walk through woods down a trail. We're staying in a loft that's above a two car garage/shed - it's a single room space, about 500sqft + bathroom and definitely the best AirB&B we've stayed in so far. It's set back about half a mile from the road too, so it's super quiet back here. Hearing lots of songbirds, but haven't seen any larger animals yet.

Maine: Day 0

Now for something different from previous posts, but probably more blog worthy - Travel! For the past two years Liz (my wife) and I have been traveling to Maine for our "anniversary". I say "anniversary" because traveling to Maine in early April is ill advised, or so we have learned. We'll be in Mid Coast region for the most part, around Camden and similar small towns, but will ultimately go back up to Acadia as well. We're in the Charlotte airport at the moment and will be flying into Portland shortly, then we'll spend the night with family there and continue our travel north.

Fun Little HP Tower

While there isn't a whole lot I like about living in Charlotte, having easy access to a place called "The Grid" is really awesome. The Grid is a store run by Goodwill, and unlike your typical Goodwill, The Grid only sells tech - computers, TVs, game consoles and games, lots of accessories - if it plugs into a TV or Computer, it'll show up there. Quite a few of their donations come from local corporations and businesses, and often really interesting hardware shows up there - it's actually where I found the then bare-bones ML350 G6. Lots of machines they get still work fine, and so they get tested and have windows installed on them, and while they aren't too poorly priced, they are priced higher than I'm interested in, especially given that I don't care for a licensed OS, RAM, or storage devices. Back in the far corner there's a series of shelves for the "as-is" laptops and desktops - stuff that is either too old to bother testing (rarely older than a core2, granted) or obviously heavily damaged. I have gotten a lot of good finds out of that "as-is" pile.

Every once in a while I have noticed these little HP consumer desktops in the fray, but often they're in too bad shape to consider. Today, however, they had two almost identical units - each for $10. A very reasonable question to ask is why on earth would I be interested in some junky $10 consumer HP desktop? Well, it's because of just how junky and low end they are. This machine is a member of the HP p2 line, likely HP's lowest-end consumer desktop - I've come to understand that they could often be found new for $200-300 or less. My machine is a p2-1334, and one could almost describe it as a netbook in a MicroATX case. The motherboard is actually Mini-ITX - no PCIe slots (not even for WiFi!), absolutely no socketed processor, and no standard 20pin power. It runs off a standard 65w 19v HP laptop power supply, which I have a few of (yay hoarding?)

It's pretty good looking from the front, if a little plain.

No power supply or slots - it's a normal MicroATX case otherwise. I find it surprising that they opted for DVI over HDMI - perhaps newer models use HDMI? Normal audio jacks, four USB2.0 on the front, two at the front, headers for two more are unpopulated. Ethernet is only 10/100 - super cheap Realtek chipset. I do appreciate that the I/O shield is a knock-out variant, I may move this board into a Mini-ITX case someday.

This should give you a good idea of how empty the case is inside. There's a single exhaust fan at the rear, and just a void where the power supply and MicroATX slots would be. The optical drive is actually part of why I decided to purchase it in the first place - I'm running low on drives that can burn DVD-DLs, and believe it or not, this one can - so I figured at the most I was playing $10 for an optical drive. I added the SSD once I got it home, it's mounted just to the left of the motherboard, on the underside of the brace. There are screw holes for both 2.5" and 3.5" drives - clearly suited for whatever was cheapest that day. Both drives are powered directly from the motherboard, and I imagine it can't handle much current - no 15k drives here. There are no mounts for additional drives, but there are a few spots where one might have mounted other accessories. One version of this case held a card reader by the front panel USB ports, but it's not populated here.

While removing the board, one of the plastic brackets around the SATA power connectors decided to come off with the cable. It did slide back on easily enough, but it goes to show that these things were not meant to be disassembled. This is a total throwaway computer.

Not surprisingly, this is a very bare board. I decided to pop it out in order to clean off the bit of dust present as well as to at least do the CPU and FCH the honor of replacing their thermal paste, which was horrendously caked on. The RAM, DDR3, is the users' only option for expandability, and apparently the AMD Hudson-D1 FCH supports up to 32GB RAM. HP's docs for the board say it caps out at 8, but I have tested it with as much as 16 myself, so I am assuming it could handle 32 - though why someone would put $150+ of RAM into something like this is beyond me.

The CPU is an AMD Fusion E2, this one specifically is an 1200, though they are apparently sold with up to an E2-1800. The TDP is less than 20w, thus the passive clip-down heatsink. I haven't benchmarked it yet, but my expectations are low.

Update: For giggles I threw Windows 8 on it this morning and ran Cinebench. Performs about as you'd expect.

Right now I have Arch installed on it, because that's sort of my go-to for new x86 machines these days. Eventually I will try Windows 8 (as it shipped) on another drive, but I don't have the patience for that right now. For what I have done on it so far (which, granted, has been very little) it feels just fine, snappy even. I imagine even with Windows 8, as long as it had 8GB RAM, this machine would be perfectly suitable for basic day to day tasks.

For reasons that are beyond me, I have already developed a very peculiar attachment to this machine. Expect to hear more about it in the future...

PS - I love that the board was manufactured by "PEGATRON" - what is that?