With Wings As Eagles: Tech/Computer/Electronics Entries


2016 August 01 16:28

My blog server had pretty severe bit rot. I hadn't kept up with the site maintenance, I'm afraid. I don't know exactly what the problem is, but for at least this calendar year, I coudln't reboot the server without serious work to get it back running again. I think what probably happened is that something in the emulation layer got out of synch with something in the packaging, and so it just woudln't boot correctly. I got the great folks at my hosting site, vps.net to get the server running again a couple of weeks ago, and so I managed to pull a full backup, but then within the last week it died again.

Ove the past couple of days I backed up the backup, so I have everything from the old server image in multiple places. Last night and this morning, I bit the bullet and had the server completely re-installed. Now I've re-installed everything from the blog. If this entry shows up (It will be the first August 1, 2016 entry) then we know it worked.

When doing stuff like that, you discover all your sins in the installation. Like the fact that the blog is all packed into /var/www like it should be, but some of the support script are in a directory in my home directory. Ooops. And the includes are scattered around in wierd places.

More on that in a while. The house is fine, the cats are fine, the plane is fine. The family is fine, and has had another (human) member added to it, which is very exciting.

All for now. This has been a systems test; please ignore. If this were an actual blog post, I'd have a picture of an airplane instrument panel or some electronics or some such.

A quick one....

2015 December 27 22:35

Photos that amuse me. I was driving somewhere and messing with the Stratus with ForeFlight.

Hell of a Year

2015 December 26 19:12

At the Cabin over Christmas. Burning paper trash here. I just liked the shot of the burn barrel and the creek.

It's been a hell of a year. As of October, all of the settings of the Back to the Future movies are now in the past. Our "Log In Date" for our adoption portfolio was mid-November, so that's exciting. We're taking Mandarin Chineese (mostly spoken, some written).

Aaaaaaand my father-in-law died a couple of weeks ago. :-( Thus we ended up here longer than expected, and we had (and still have) lots to do. Oy. An ugly transition. Very sad. We're still getting used to it.

So I'm going to try to get posts up that summarize the interesting bits of the year. Here's the one for this trip.

One interesting thing: my wife and I gave this record/CD/tape player/radio to my father-in-law in...it must have been 2002. I tried to play a CD in it, and the drive is jammed. Apparently he used it so much that he wore out the drive mechanism. I'm incredibly gratified.

This is the back of the Explorer about to head back from the memorial service. The cylinder on the right is a 1/6th keg of beer, so that we wouldn't run out when all the people came back to the house. We swapped it in before the night was over. People got a kick out of my walking across the road to the liquor store and bringing the keg back with my funeral clothes on.

And I got some Taurus driving in while running errands; some day driving

and some night driving:

And I got to drive the Explorer a bit. It's fairly new one, so it has the fancy digital dash.

And the climate controls are complicated enough to launch a space ship.

Charging back-up cell phone batteries. The cable is obviously better because it has glowy lights in it. :-D The charger is one of the a great set of Sprint chargers that are both car chargers and wall chargers, and they have lights on them.

My Christmas present to my self is this comically large tap handle. I got this because I'm going to tap the engine block of my VW for an oil filter, and the tap is large enough that it doesn't fit in a normal tap handle. The beer can is for scale.

I was sitting on the couch studying for my Chinese language final. This photo is absolutely not posed; Jasper came, sat down with me, and put the royal paw on my books. I think it's a hilarious pose; it's great that he looks so stern.

I've had a long-term project around the main floor of the house to kind of get my stuff organized in a longer-term way. I like having a working desk that I pile stuff on to work on or sort, but of course that gets piled up. So I cleared out this drawer, so it can be the "to be sorted" or "to be gone through" piles, so it's out of the way. Of course, as is no surprise, Pangur is helping.

All for now. More entries on the year as I get photos edited.

What I've been doing...

2015 April 28 23:00

I meant to come and have the annual of the plane take 3 or perhaps 4 days. *sigh* It's not super-bad, I get to stay and play with the parents-in-law who are awesome, but it's been two weeks as of tomorrow and I miss my wife and cats.

This post is about what I've been doing. Early on we cleaned and check spark plugs; everything looking healthy there.

One of the big things I've done this trip is take all the belly panels off my plane for the first time. Here they are laid out with piles of screws.

I forgot to put something in the picture to scale; the panels are about 2 feed wide, top to bottom in the image. There's about a few hundred screws holding them to the airplane.

Getting the screws out wasn't trivial. Three of them had actually completely frozen, so I had to cut a slot in their heads with a dremel tool to get them out.

Another thing I got to mess with was taking off and putting on the spinner.

I painted the pressure plate (highlighted by the red arrow), and then installed the forward bulkhead with new screws. Just waiting for the mechanic's approval to put that part back together.

So what's the fuss about? Why did I stay longer? Well, I needed to have a spacing collar installed in the nose gear for better handling. THe collar is the silver ring; the white plate is the pressure plate at the top of the gear doughnuts.

And as long as we're taking the nose disk shock tower apart, I decided to have the shock disks in the nose gear replaced.

Also, while I've been driving back and forth to the hangar (1 h 20 min each way) I've been testing chargers to see which one worked best charging my iPad mini.

So tomorrow, hopefully by mid-day the nose gear will be back together and I can start planning for the trip home.

Installing the Stratus

2015 April 07 10:04

Here's what I've been doing with the Stratus. Here's my working cardboard template that I'm getting into shape.

I'm basically making a basket or tray that holds the stratus along the axis of the airplane, so that I can see the status lights, and so that it doesn't slide off into my lap from the glare shield. I did this very early in the year.

A few weeks later, I put together a more precise version of the tray. Here I've put it together.

Eventually the thought is to make the tray out of Aluminum so it's stiffer, but the cardboard will do for a short-lived version.

The green cord is a USB power cord that runs along the top of the glare shield and then comes over by the pilot to power the iPad.

The cardboard tray, cable tied into place on the compass mounting tube, with the Stratus sitting in/on it. And the power cable to the Stratus:

Here's what the setup looks like from outside the windshield:

If I park the airplane just right, I can get the car into the hangar with the airplane still in it and shut the door:

A closer view of the above shot. You can see the oil cooler nicely here in the lower corner of the cowl. You can also see the Stratus in its mount under the windshield.

And after a couple of hours of futzing and prepping, the airplane is ready for its trip to Texas (another post).

The weather was likely to be fairly cold the morning that we left; you can see the extension cord going in the oil door on the cowl; it's attached to the engine heater plug and comes from a timer on the other end. I set it to start warming the oil several hours before we got to the hangar. It worked great.

Charging: going forward

2015 April 06 22:40

Last year sometime, I bought a charger to go in the airplane. It has three outputs, with different current capacities marked on the USB ports:

It worked pretty well for my accessory electronics in my airplane while I was flying. The 2.4A output was enough to charge the Stratus GPS/ADS-B unit, and the lower 1.5A output would charge my iPad.

Well, I got another one to charge the two devices, a newer one without the labels, with the hopes that since all the outputs were the same, it would be able to supply full output current to all three outputs.

Not so much, it turns out. Only output that can charge the Stratus is the top on, and the other ports act the same as the labelled one. So in other words, the unlabelled one is the same as the labelled one just without the physical labels. Oh well. More recently I've been investigating other charging solutions. (Both of the 3-output white chargers are "Bolse" brand.)

One interesting thing I ran into while testing the newer charger was that if I pushed it into the power socket (formerly lighter socket) all the way, it would trip the breaker. Looking inside, you can see why:

The yellow dot indicates the tang on the hot part of the socket. You can see it's scored on the edge where it's touched the side. I suspect that someone put the back part of the socket from a car into the socket from the airplane. This is something I'll have to talk to my mechanic at annual (which is soon). My temporary solution is the red cardboard strip that keeps the tang from touching the grounding barrel.

The reason that I'm getting the charging stuff set up is that I bought an iPad mini 2 for my electronic charts.

Next to my hand is my old iPad 1 that I've had for a few years, and farther away from my hand is the mini. Both are running foreflight here.

I have a RAM ball mount on the bottom of the pilot's yoke in my airplane. I have a RAM mounting arm and an iPad mini mount to hold the mini in front of the yoke. Here you see how I've modified the arm, so that the arm will sit up flush with the yoke shaft:

And here's the iPad mini on its mount on the yoke. This is basically my view sitting in the pilot's seat.

The full-size iPad is pretty bulky, but the mini is perfect. I can read the approach plate (as shown) but I can see the panel and switches just fine. I've flown four big cross-country flights with it mounted this way, including a real instrument approach in significant IFR conditions, and this worked great.

Oh, and another thing: The Bolse charger wasn't able to charge the Stratus and the iPad mini continuously for all the flights. Sometime during the second flight, it stopped charging the stratus. I don't know if it gets too hot or what, but the flights were finished under battery power. Which is fine, but I wish I could get a solution that would continue to charge for arbitrary amounts of time.

I realized the other day that I don't have any ANY photos of the airplane in the last dozen or so blog posts, here here are a couple. This was March 1 when I went out to the hangar and test the fit of the iPad and test the charger. After two weeks of basically being snowed in, we were able to get out of the house, but the hangars still had a ridge of snow from it falling off the roof of the hangar building.

And just because it amuses me, a closer version of that same photo:

I love the asymmetric look of the nose, the landing light on the right side and the oil cooler on the left. If you look closely, just to the right (from our point of view) in the windshield is the Stratus taped to the glare shield. The saga of the mounting technology for the Stratus is another post entirely.

March part 1

2015 April 06 07:23

Wow--March was quite a month. Even in January, March was already shaping up to be a busy month. I had significant trips/commitments early in the month and late in the month. Then I had the bright idea to stick a really busy work trip with personal travel on both ends in the middle. So March was very busy with travel; as I write this on April 6, it's just finally settling out and this week should be back to a normal-ish schedule.

The first journey was a trip up to Cincinattii to help my wife run a conference. This was an absolute committment on my part, and has been on my schedule for at least six months. The two weeks of snowmageddon at the end of February were not encouraging for this trip. The conference was Friday/Saturday. Earlier in the week, the state of Kentucky wasn't doing too badly, but it was looking a lot of the state would get snow dumped on it on Wednesday and Thursday, so us just getting to the conference was looking iffy.

Given the snow that was expected to land on Thursday, if we started heading north on Thursday morning, it was likely we wouldn't be able to get out of town. So we decided to outmaneuver the weather. Wednesday afternoon (in fine weather) we drove to Lexington and stayed in a hotel right on the north side, next to the interstate, so the roads we would be driving on would have the best snow removal possible.

That worked fine. But we did get the expected snow over night. When we got up, the car was caked with nigh on a foot of snow:

That morning, I did the first clear-start-scrape-defrost cycle I've done in many many years. I know people in Minnesota do that every day in parts of the winter, but it's been a while for me. I also backed it across the parking lot so that it was clear of the snow piles around it. The end result was pretty good:

While we were having breakfast I made some poor attempts at bird photography while we were having lunch.

Due to the higgledy-piggledy of the snow and its effect on the conference schedule, the conference days itself were super-busy, so I really don't have anything to show. One really nice thing: right across the street from the hotel was a Joe's Crab Shack:

I think if I were reviewing that as a design for an establishment in a game, I would perhaps ask them to pull back the character a bit.

And last thing: on the way home, I saw this advertisement in a truck stop bathroom. It got me thinking more about car (and also airplane) USB chargers, which is another topic that I've been working on this past month.

So the trip to Cincinatti was the opening salvo of the month. The big trip in the middle of the month was yet to come.

Now with a new platform!

2014 December 07 09:39

The fall has been good, but busy. Work is good, the fall conference went really well. There have been a couple of changes, so I don't have photo editing and uploading sorted out yet, so this post is text-only.

The plane is doing superbly well. I took two signifnicant trips in it, in October and November, and absolutely NOTHING went wrong. This was a first. So I'm beginning to trust it much more for trips and such. The one last thing I want to do for this winter is to install an engine heater, so that I can electrically pre-heat the engine when it's cold. That will make life easier on it.

I didn't work on my old Beetle at all this fall, but I've started doing that again recently. I'd like to get it back in commission in the spring. I'm going to rebuild the engine, and now I'm working on assessing exactly what parts I need. The crankshaft is reground and I have new bearings. I was convinced recently that I probably really do need a new camshaft, so in the last week I've been working on assessing what exactly I need. I'll have another post on that soon.

I got a new phone early in the year. The way it mounts as a drive is different than older phones, so pulling photos off of it is different. You can easily pull images from folders that you've created, but it doesn't seem to want to pull images directly from the raw camera volume. That technique worked so well for so long; I don't get why that needed a whole new protocol. :-/

And *just* recently (Wednesday) we got new laptops. My wife was looking for one, and pinged me about a deal on Amazon. I liked it enough that I decided I wanted one too. They are Lenovo X140e Thinkpads. So I've gone away somewhat from ultraportables, but it's a relaly nice laptop, and not TOO heavy, with lots of battery life. I'm typing on it now. More keyboard throw and sound than I'm used to, but it's not bad.

More soon, but I at least wanted to get something up here.

New Pretty Gauges

2014 April 24 21:55

I was planning on blogging every day in April. Ha. I got busy and went to the MAPA convention and got delayed (again) until I could fly the plane back and I've just been busy. I should stop promising to do that.

Anyway, the airplane is physically flyable, annualed (so it's legal to fly) and back home. Yay! Here are a few photos of the gauges while flying back the last leg from Bowling Green.

Here's the stock 6-pack engine cluster.

The upper right gauge, the old ammeter, has been replaced by a new digital one (see next photo) and so it's marked INOPerative. The important thing here is the bottom three gauges are all firmly in the green (actually, the cylinder head temp, the lower right one, is basically below; this plane cools superbly well at cruise).

And here's upper-right side of the instrument panel:

In the lower left is the stock manifold pressure gauge and fuel pressure gauge. In the upper left is the new Horizon Tachometer. I really like how it looks and how it works. The area in the center was a blank panel up to this winter's annual. The orange engine meter (bar graph thing in the center) was all the way over on the right where the blank round panel now is. I moved it closer so it's easy for the pilot to see it and get at the switches. The third meter, the one with the single switch right below it, is my new volmeter/ammeter. I got it because the stock ammeter just didn't read very well.

The area in the center that's shinier black is a panel that I fabricated. The engine monitor is an older electronics piece, so it's fairly long and kind of heavy. THe extra screws that you see in the panel are attaching reinforcing rails to the back of the panel. Two of the breakers are for the new instruments. The third is for the engine monitor; it had been protected with an in-line fuse from the avioincs panel, but I wanted it on all the time, so I instead put a breaker and now it's powered from the main bus. And in the upper right is the control/sense plane for the new ELT (emergency locator transmitter).

Box-shaped Beacon

2014 April 05 09:46

Since we decided to have the engine overhauled for our airplane after the prop strike, and the airplane was going to be up for annual anyway, I figured that was a good time to take care of all the stuff that needed to be worked on and that would take calendar time, since the time was incurred anyway.

One of the things I knew was up was the ELT batteries. Every civil airplane in the US (with certain limited exceptions) is required to have an "Emergency Locator Transmitter" (ELT) on board. This activates if there's a sudden shock (because of a crash) and transmits a signal so that search/rescuers can locate the plane by radio signal. The ELT is internally-powered by batteries. Modern ELTs are supposed to have a panel in view of the pilot that allows the pilot to turn it on or off, and indicates whether its transmitting. In any case, I knew that the batteries in the ELT were due for replacing this annual anyway.

My plane didn't have an ELT panel, so I'd been thinking about that. So when I was at Oshkosh last year, I bought a used ELT (very cheap) with a new install kit. First, I thought that it would be interesting to look inside and see how they worked. Second, I though perhaps that the install kit would allow me to put a panel in properly.

So, first step was to look at the old ELT and replace the batteries. It turns out that there were problems with the old one; it had broken mounting. Its batteries were also the style that had to be replaced by a specialized battery pack, not with off-the-shelf batteries.

So I asked my mechanic if we could just use the used one that I'd bought, which, as it turns out, can be batteried with Duracell D-cell batteries. He said it was fine to do that, as long as it tests out correctly. The one thing I needed to do was to clean off the battery terminals. At some point someone had left batteries in it too long, and the terminals were a little green.

So here are the battery terminals, nice and cleaned up and shiny:

Here's the ELT sitting on the desk, batteries in and tested. The cord is plugged back into the ELT itself to act as an emergency carry strap. Patches the airport cat looks on.

Here's Patches inspecting the left wing navigation light.

One thing I had to do was run the control cable from the back of the airplane where the ELT sits to the control panel, which I installed in the front instrument panel. Here's the left side of the body, with the interior mostly out, with the cable (which is really a phone wall cable) installed and indicated with red arrows.

And here's a close-up of the center section:

And finally, the ELT installed and ready to go, with the cable plugged in and the unit tested.

Where Does Tab-A Go?

2014 March 02 16:05

Every since I bought my airplane, I've wondered how the avionics switches were wired in. There are three electrical busses that are original to the aircraft, and then an avionics bus. There are two switches to turn on the avionics bus; the main one in front of the pilot, and an auxiliary one on the other side, next to the avionics breakers.

Durin gone of my checkout flights, my instructor and I were flying and wondering about debugging another problem. I had the main avionics breaker on, and we wondered about auxiliary, so we turned it on as well. A couple of seconds later, it turned off (it's a breaker-switch). We didn't know why it did that, so we left it alone. I've never touched it in the air, but I've turned it on on the ground a couple of times.

But ever since then, I've wondered how it IS wired, and why it behaved the way it did. Generally if you turn on two switches in parallel, they'll each carry less current and so be LESS likely to trip.

However, I think I've figured it out. Here are a series of partial electrical system diagrams. I cut out the bit of the diagram from the origianl maintenance manual for the airplane. There are three busses. The bus on the right is the "main" bus, and that feeds all the loads that are always connected. It feeds the electrical turn coordinator, and the interior lights, the lighter socket, and so on.

The bus on the left is the "auxiliary" bus, which has all the stuff that the pilot turns on and off. Landing light, navigation lights, strobes, rotating beacon, heated pitot tube, electric fuel pump and that's where my primary avionics bus switch is. The bus in the middle is called the "power" bus. It connects to the battery, to the generator, and then feeds the other two busses. In both cases below, I've circled in red the tie point where the battery and generator connect to the power bus. It's not important except that's where the current comes FROM in all cases.

One of the breaker switches on the left bus feeds the magenta (purple-ish) wire that then feeds the avionics bus up on top. The black wire on the left goes from the main bus, through a separate breaker switch (the avionics aux) and then to the avionics bus.

First, here's how current flows to the avionics bus normally. The main avionics switch (on the left bus) is turned on, the aux avionics switch is turned off, so the black wire on the right doesn't carry current because it's disconnected. Current flows (marked with red chevrons) from the power bus through a wire to the left bus, then through the main avionics breaker switch through the magenta wire to the avionics bus.

If the main avionics switch is turned off but the aux avionics switch is turned on, here is the current flow instead. From the power bus to the main bus up the black wire, through the aux avionics switch to the avionics bus.

If BOTH avionics switches are turned on but there's nothing else in the system consuming current, then the current flow looks like the following. Some current flows through each breaker and along each wire. Although I haven't tested it, I believe in this case that both breaker/switches would stay turned on (wouldn't trip).

However, here it gets much more interesting. If, say, you had some things on the left bus turned on. This would be consistent with my circumstances when I was flying with my instructor; we were on a long cross-country flight with some clouds, so I probably would have had the nav lights and strobe lights on, at least. That's 10 or 12 amps coming off the bus on the left. The current flow is something like this:

There are now TWO paths for the current to take to the left bus to feed the lights that are on. One is the normal path from the power bus to the aux (left) bus. However, current can also flow to the main (right) bus, through the black wire, through the avionics aux breaker/switch, then from the avionics bus through the magenta wire to the aux (left) bus (opposite the normal direction of flow) and then to the aux bus and then to the lights. How much current flows in each branch is difficult to determine, and depends on the details of the wires and connections, but no matter what, some current is flowing through the aux avionics breaker switch that shouldn't be, and so its current burden is higher than it ought to be.

Oshkosh 2013 3 of 5

2013 September 15 12:21

This entry is pictures of my camp site at Oshkosh and the charging implements that I brought along.

Here's where I camped, at the west end of the North 40. The position is being indicated by he Stratus GPS.

The inital unloading:

As a historical note, the weather at the time I landed was ASS cold. Something like 43 degrees F and windy. And I didn't have anything with long sleeves, because Oshkosh tends to be hot or humid in the summer. While I was unloading and pitching the tend, I wore my headset. I looked like a big-ol dork but at least my ears were warm.

I tied the plane down to "The Claw" anchors.

The knot securin the rope to the anchor is a double-bowline.

The top of the rope is tied to the plane's tie-down loops with two double locking half-hitches.

I pitched the tend behind the right wing facing the fuselage

as close to the wing as I could make it.

That way, I could step out of the tend and be at the luggage door in about two steps, which was nice.

My walkway in and out was between the horizontal stabilizer and the tent, which isn't ideal, but it worked, and kept the whole camp site fairly compact.

I realized I was going to be mostly away from plug-in electricity, with my phone and laptop and camera. In the past, I've brought a big battery pack to charge things from. Those dont' last very long, though. So this year I stopped by Harbor Freight and bought a brief-case size fold-out solar panel, with fittings so that I can connect it to car chargers to charge my gear.

Here's the briefcase solar panel sitting on the tail catching the morning sun:

On the wing getting the mid-day sun

And then on the windshield to catch the late afternoon sun

The solar panel has a cable attached to it, that comes in the lower right to the plug at the bottom center:

The it plugs into a car-charger-type socket (top center). Then there's a car charger at the top center (with the blue light), into which is plugged a usb cable which then charges a device. Here's another charger charging the Stratus unit:

There are charging stations around; there's a big one at the North 40 shower house. Here's someone who has a battery back like I had who had plugged them there:

EAA had other places around the grounds for this function too:

Honda combined this concept with advertising both for themselves and their generators by putting stations like this around the grounds:

This is a running generator with a couple of power strips on a little platform. It also had several chargers and cables already. I plugged in and charged my phone at one of these a couple of time. This station was right by the food court, and it was well-used.