We are the people who work on old things

Yes it’s true, we are now the people who work on our old boat and we used to be the people who worked on our old house.  Plaster, woodworking, repairing marble surrounds, copper flashing and mission tile roofing, replacing galvanized pipes for newly soldered copper ones, refinishing floors, repointing bricks, reglazing windows, and restoring intricate plaster crown moulding.  That was then: the house.  This is now: the boat.   Someone really introduced us to another couple that way “those people who work on their old wood boat.”  At the time it made some sense because when we were in a slip it was because we needed shore power to work on the boat more conveniently and when we were sailing we were “out there” and absent from the view of the particular fellow.   It’s an interesting life–being the people who work on their old wood boat.

But right now all I can think is “Buttercup, oh Buttercup. How many ways can you make my life interesting?”  David and I recently took Buttercup for a “spirited ride,” let’s call it. A Sunday, a glorious day of driving our 1976 Saab 99 on winding roads, dirt and paved, up hills and over mountains, and along the seashore just as Buttercup loves to be driven. The drive was a ‘post tuneup check’ to see how she was doing.  She was to have her state safety inspection the next day and I needed to make sure she was in good form.  With little bits of rust here and there, the old girl is not looking her best and it was all the more important that she pass the inspection with flying colors.

On the drive we found all was good with Buttercup except we noted the rear shocks had seen better times and further since the ball joints I’d ordered from Rock Auto had arrived, it looked like we’d be spending a day working underneath Buttercup sometime very, very soon. We’d just need to find someone to do the alignment.  As an aside — Rock Auto has amazing deals on car parts for, shall we say “elderly” cars.  A further aside, Buttercup did pass her safety inspection just fine — more or less an emissions check, the inspector must still make sure brakes, lights, and all the rest work.  Lucky for Buttercup they are not as picky as we are and they didn’t do the big sideways jiggle/push/pull thing we do on the front wheels or they’d have noted the tiny bit of a giveaway that her right front ball joint wants to be replaced and they didn’t take her on a spirited drive or they’d have known her shocks weren’t up to snuff.  Fine for normal driving but not so great for rutted country roads.  

Gone are the days where one can get a selection of good shocks for any USA-based pre-1978 Saab model 99.  Having owned our 1974 Saab 99 Pepe for his last 34 years and 400K of his half a million miles (1982-2006) and Buttercup since 1998, I know a little thing or two about shocks for the model.  Before we owned Pepe, David’s father owned the car since it was new.  David had cajoled Dad into many things that were lifetime warranted to the purchaser — and since David did all maintenance for Dad on Pepe, that meant David owned the lifetime replacement guarantee on let’s see…a JC Penny (later Firestone) battery, lifetime alignments, and even lifetime warranted Koni shocks.  We used those on Pepe for about a decade during which we re-valved a few times and then gave up. The lifetime warranted Bilstein shocks? I blew through those on our Saab 900 in less than a month. Replaced and ruined again within weeks.  Let’s not talk about the 900 for now.

Back to shocks for the 70’s era 99 models. For our Mexico jaunts in Pepe, we used different springs, lifting kit/spacers and I obtained Bilsteins meant for a particular import truck with the same vertical pin shock mounting system and a little different range of motion. Alas while that was good for our ’74 99 for many back road excursions in the 80’s and 90’s it likely contributed to every shock mount point being ripped apart (on the road) and rebuilt (in a local welding shop nearby) a few times…even those trusty (lifetime warranted) shocks were rebuilt a few times and swapped out with the Konis on Pepe until finally I gave up on them when we said our farewells to Pepe in 2006 (RIP.)  Buttercup, with her original 1976 axle is stuck with those same old-style shock mounts.  When we got the car, we put the Koni shocks on her, or maybe it was the Bilsteins — whichever ones that were not on Pepe.  A few years later we threw some KYB shocks on the car thinking “we’ll find something different, later” and so now is “later” and we see that shocks for this car are available from only a few makers.

Though David reminded me that KYB really just means “keep your Bilsteins” I had decided I’d just get some decent KYB shocks for Buttercup and probably just needed to find a local sale.  It’s so hard to justify more than the basics for Buttercup when we drive so few miles and well, we try to keep the maintenance funds together for Mahdee’s much larger appetite.  These old ladies vie for attention, that is for sure.

Yesterday when suddenly Buttercup’s passenger rear side started making a clunk-clunk-clunk over rough road spots, I thought “hum, I’ve heard that noise–the shock bushing just popped off top or bottom of that shock.” David and I both have a lot going on right now and I hate getting dirty anyway so I also thought “I have an excuse to get someone else to replace these shocks! I’ll take the car by the local auto parts place” where I’d recently seen they have a model of decent KYB shocks “and I’ll have them put a set on the rear of Buttercup.”  I texted the same to David.  He came back with “sure, ha!” implying the shop couldn’t do the work.  I won’t say he jinxed it but I will say he was right.

I looked at the estimated cost and almost just bought the shocks and took them to the workshop to install myself.  But I hate getting dirty.  I have mentioned that? It’s always dirty, gunky, yucky work to get the nuts loosened up and off of the top and bottom pins of the shocks.  It’s sometimes really difficult to do, as well.  Wesley is playing “garage king” in the workshop while we wait on an electrical part so the logistics of getting Buttercup into our workshop would involve me PUSHING Wesley out of the way…no, no, not going to happen because then I’d have to push Wesley back inside the workshop, too.  The car is heavy and there’s a lip on the concrete sill that I would find difficult to deal with.  Therefore installing shocks on Buttercup would mean doing the work outside the workshop door rather than inside. Outside on the pebble-strewn, dirty, gritty asphalt.  Nope.  Not going to do it. Nope.  And David was tied up all afternoon with other things–so much the more perfect excuse to just pay someone to do the work.  The only things Buttercup has ever had anyone besides David and I do? a couple wheel alignments when we’ve replaced tie rods or ball joints– and we had a gas tank lining installed once.  Lifetime warranted lining, I might add.  Old habits die hard.

As I was filling out the paperwork for the shop to replace the rear shocks, I wrote details of the noise and then wrote “please report whether the top and bottom bushings were in place on old shock rear passenger side and if both are in place, please do careful inspect the rear suspension, panhard arm bushings, shock mounting points, and related that might produce a clunking noise from that area.”  No work on the front suspension requested.  I  knew they’d be likely to note the right front ball joint and was in enough of a hurry that I didn’t want to deal with a full suspension inspection by them.  Because Buttercup still has her reverse lock intact, I also gave them the standard Saab bit about “key between the seats, car must be in reverse to remove key, reverse lock is annular ring around shifter knob, pull up on ring while clutch is depressed to put shifter into reverse.  Only try to remove key once the car is in reverse. Do not remove key if you cannot get car into reverse.  Just leave key in ignition if you experience any problems.”

I sat in the waiting room an hour, anxious and unexpectedly worried about that reverse lock–playing the game of odds: will they break it or not? Thinking how ridiculous it would be for this car to have survived 41 years of driving without the reverse lock being broken and having it get broken now.  The service manager came out to the waiting lounge, handed me the paperwork and said “we can’t fix your car.”  I said “fix? what fix? do you mean install? Do you not have the shocks? You cannot install the shocks?”  and he said “No, we can’t fix you car.  There’s too much wrong with it.”  I asked “what’s wrong? Is a shock mount to the body ripped out?”  thinking that even though the shock itself seemed fine, my worst fear was true and I’d have to find a local welder for the work.  “No mam, there’s just too much wrong. ”  Now I was perplexed. I asked to speak to the mechanic to find out what “everything” was.  After all, I already knew about the ball joint… maybe he was looking at the front end, not the rear suspension. I actually knew that we should replace the brake pads sometime in the next few months.  We do that as a preventative though.  Brakes are not suspension…he couldn’t be thinking about brakes?  The hard to find MetalMasters are on back order and will be here in a few weeks.  My mind went automatically spinning through the logistics of going ahead and bleeding the brakes at the same time as doing the pads. Solid rotors made for different pads.  I really like the vented ones.  No reason to change them though. But I really like the vented ones.  Finding a place to take the old brake fluid.  Does O’Reilly’s do that? How about the US Coast Guard Auto Hobby Shop? But bringing myself back to reality, today! The brakes would be no reason to say “too much wrong” and not install new rear shocks.

The mechanic, a small Hispanic fellow, came out and said “the car, it pulls a little to the left when I push hard on the brakes but other than that I could find nothing.  I don’t work on old cars.  You should take the car to the people who work on old cars.”  I ask him “what about the bushings on the top and bottom of the rear passenger shock?” and he says “the bushing is there.” And I say “did you see any other missing bushings? Panhard arm or nearby anything?”  to which he says “no.”  And I ask why he didn’t go ahead and replace the shocks.  I learn that again “I don’t work on old cars, you should take the car where they work on old cars.”

So an hour wasted and I still don’t know what is causing the clunk, clunk, clunk.  As I got in the car I noted the key was in the ignition, turned to the position to keep the radio on, the car was in 2nd gear.  Guess the guy didn’t read the instructions but thankfully he didn’t break the reverse lock. I look at the time and realize David is likely on his way to the boat very soon, riding right past our workshop, so I text David to meet me at the workshop and I drive the few blocks there.  Took a look under the car.  Missing shock bushing as suspected.  Drove the two blocks to the O’Reilly Autoparts store to purchase something to use for shock bushings thinking “we have these things somewhere… but it would take more time to find them than to buy them.”  A four-pack of generic bushings is $4.49 plus tax.  One bushing needed.  Three spares for the glove compartment.  I wonder if I’ll remember they’re there in a few years when they may be needed? Jackstands and chocks in place, David laid in the gravel and grit on the asphalt and got gunky greasy fingernails while installing the cheap bits of rubber. He has a big loopy grin on his face.  He’s happy–but won’t admit it–that the mechanic didn’t work on Buttercup.  I wonder if he even notices the dirt?

We put David’s bike in Buttercup’s trunk and drove together to Mahdee.  The clunking is completely gone.  I mused on the way home thinking of what the mechanic said “you should take your car to the people who work on old cars.”

We are the people who work on old cars.

Repair to the bowsprit

A couple weeks ago, David and I took Mahdee out for just a little Sunday morning jaunt between rain showers. Funny how a few minutes of inattention can turn into days of repairs later… Yes, somehow a bit of wood had managed to get beneath the shipping bowsprit in such a way that when the spar was lowered into position, the stresses applied managed to split the foot of the bowsprit. Is there a good thing? well, when the spar is in use, it is in compression upon a pin forward of the damaged area so the damaged wood isn’t loaded up at all. Bad thing? it added another repair to our list of “things to fix” and this one required sooner rather than later.

Before going further, let me get into a little discussion of the bowsprit’s purpose. Many people wonder why schooners tend to have bowsprits. So what is its purpose? To bring the effort of the furthest forward sail, the jib, the proper distance forward to get rid of any unbalanced helm–weather helm–caused by the schooner’s large mainsail but not so far forward as to create lee helm. That probably sounds like a bit of gibberish to some of our friends. For our non-boating friends, I’ll explain further: When sailing a boat with an unbalanced helm, it is somewhat like driving a car that needs wheel alignment. You can’t let go the wheel lest the boat quickly spin up or downwind depending upon the balance of the sails. The boat’s underwater hull shape, heel angle, as well as position of the sails in use at any given time can create the unbalanced “weather” or “lee” helm. The wind’s force on all the sails aft of the boat’s fore-and-aft center of gravity (CG, a pivot point and there are more than one CG since we have a fore-and-aft CG as well as a vertical CG and just to confuse things a bit further, sometimes people call the center of effort of the sails the CG as well) tend to point the boat up into the wind, to weather, whereas the wind force in the sails forward of the CG tend to make the boat fall off away from the direction of the wind, to lee. These windward and leeward tendencies are called “weather helm” and “lee helm.” When sailing downwind, we love to have lee helm as it keeps us pointed properly and so we can put lots of headsails up and leave the mainsail down, enjoying the ride. Other points of sail are not so easy for balance for most boats. On the day I videoed my solo watch (see embedded video here), you may note the wheel doesn’t turn at all — it is locked into a single position but we’re gloriously sailing downwind.  This is because I only have up the foresail and staysail, both have center of effort forward of the boat’s CG and creating just enough lee helm that when the waves push us around a bit, the wind in the sails keeps us pointed running downwind.

Since the hull shape makes a boat’s in-water resistance change the exact position of the CG, it isn’t really obvious and visible at all. The CG on an individual boat can vary with the boat’s loading.  Loading can move the boat’s CG fore and aft–a heavy bow with too much anchor chain or heavy stern with too many fuel tanks and batteries for example rather than exactly as the naval architect intended will change the fore-and-aft CG. Even before we load her, Mahdee tends to be a bit stern heavy and has a cutaway forekeel forward and a deep keel aft so her tendencies are a bit…aft…to start — Crocker’s calculations of CG show her CG a few inches forward of the aft-set mainmast — and then we seem to have a bad habit of loading her up with full fuel tanks aft, supplies midships, and while we try very hard to load up the forecastle with extra anchors and whatnot, we must admit we contribute to the weather helm situation if we’re not careful of how we load her pre-voyage. Her ideal load is with mostly empty aft fuel tanks coupled with a lot of spare water cans sitting in the forecastle. Note “forecastle” sometimes spelled fo’c’sle is pronounced “foksol” like… “folk soul” by most people.

When we use the foresail and staysail alone as we do in big winds when we’re trying to be cautious and importantly trying to not tire out our double handed crew, the jib on the bowsprit stays in the nets. But when we raise the mainsail, the jib is a requirement and the bowsprit a very important spar aboard Mahdee. So after the “crack” and “oops” sounded simultaneously, we knew we had to repair the bowsprit asap. I decided I would paint the ‘sprit while it is removed since it has a few rubbed spots and dents in need of care. It was painted in 2009 and the last time it was touched up was in 2012. After the damage, it rained all the following week. Good friends from DC visited the next weekend and we explored local house museums, eateries, and parks with them for three days. Then with Buttercup and Wesley vying for attention and smog checks coming up, time flew by with us elsewhere diagnosing car issues and focused on their needs. Buttercup’s smog check completed and Wesley stuck non-opp and waiting for parts, we were finally ready to do the bowsprit — three busy weeks had flown by and last Sunday evening was the first moment we could have at it with the bowsprit. The sun was setting and knowing the next few days would be very busy and then rainy, David said “now or never.”

Our rig has twin forestays at the stem, so taking the shipping bowsprit off doesn’t impact the rig as it does on many boats but it still was a bit of a jigsaw puzzle to bring the ‘sprit onto the foredeck without taking all the hardware off of it. I was game to remove the hardware, David, not so much. He dislikes doing anything he perceives “unnecessary” and he perceives removal of the hardware as that. Of course, as the person painting, I think of the ease of painting the ‘sprit with no hardware as much better than masking off hardware and dealing with wood-to-bronze interfaces. With time fleeting and the sun lowering, David’s method ruled because it really was a matter of doing it then or waiting for some indeterminate time before we’d both be available to do the removal together.

It took a bit of digging to retrieve the beat up plastic sawhorses from beneath the fenders, lines, oars, paddles, and other stuff we store in Mahdee’s forecastle. The 105 lb CQR was removed and the chain brought inboard — I ran the trusty electric windlass so it took up the load and kept me from having to do any heavy lifting. Then, the bowsprit shrouds called “whisker stays” were removed from the tip, the jibstay released, and netting released from a few spots. We’d lowered the bowsprit over the marina dock so this was all done by David working on the dock with arms stretched high overhead — almost not quite able to reach the fasteners and clips releasing it all but with no step stool or ladder, the only choice.

Then the bowsprit was swung up vertically again to allow us to remove the big bronze pin, a bearing surface, at the aft-most foot of the sprit. Pound, pound, with a hammer and old screwdriver used as a punch, the pin slid out of the bronze sleeve we’d made for it during our bowsprit repairs in 2009. With the jib halyard attached to the front and the staysail topping lift to the aft end of the bowsprit, David skillfully threaded the heavy bowsprit between the twin forestays and onto our wobbly plastic sawhorses while I cringed and kept the aft end from swinging wildly around. Once settled onto the sawhorses, an extra line was wrapped onto a cleat on it and attached to a nearby pin rack on the fore-shrouds to keep the ‘sprit from swinging inwards and smacking the foremast if the sawhorses failed, and we both let out a big “whew” and sigh of relief that we’d not damaged Mahdee while bringing the spar inboard and we still have a half hour of fading light.

It is bit over 17 feet from the stem to the breakdeck and the spar sits along the entire distance. Amazingly long. When shipped into the vertical position or lowered out the front of the boat to hang over the water, I never realize how truly long that spar is. The few times we’ve entered marinas without it shipped inboard, I’ve worried about thwacking a dockbox or another boat, of course!

David had a busy week away from the boat, so on Monday I glued up and clamped the damaged area and was quite pleased with the tight seam. On Wednesday I added a bit more waterproof wood glue–Tightbond III–to a couple small cracks and then ignored the spar during the winds and rains of Thursday, Friday, and Saturday. Now to sand and paint the bowsprit before re-mounting it on its hinge pin and attaching all the fittings to it so it can be used again while sailing.

Masts and Chocolate for the DIY-er

Trader Joe's Chocolate Cube Varnish Container
What do these two have in common?  Very little except those masts need “refreshing” aka repainting or at a minimum a good buff and wax and the chocolates are essential to successful application of paint and varnish.  See the connection? I’ll admit it’s pretty slim.  The masts get touched up with paint, buffed, and waxed next weekend since I completed the varnishing last week.

Now about the chocolate, you see, we tend to buy our chocolate in various forms from Trader Joe’s.  In these seemingly identical clear plastic cubes throughout the year.  If you don’t buy the chocolate, you don’t get the cubes. I keep the cubes because they make a great varnish container.  This one, from last year, reminds me that Trader Joe’s no longer sells the lovely Orange Sticks.  It was our favorite: orange jelly center covered with dark chocolate.  They tell us they’ll have it again someday.  We don’t believe them since it’s been a year now.

Actually, those cubes will give you pretty much a perfect varnish container if you take a couple Popsicle sticks…ummm…let’s digress a little bit more about where the sticks come from:  you get the Popsicle sticks in the summertime when it’s hot and you’ve just got to have a lime-bar.  You save the summertime Popsicle sticks for the fall varnish-fest.  You also save the plastic cubes that your Trader Joe’s chocolate came in for the same varnish-fest.  This really doesn’t take much space–even aboard a boat–just a tiny little spot in my project bin where the cubes can stack and the sticks can stand next to them.

Then, in the fall, you pull these things out because you’re ready for your paint and varnish-fest to protect all the exterior woodwork through a winter of rain or worse inclement weather.  You grab a cube and take a thin plastic baggie–of the sort that nobody buys because it doesn’t ziplock but somehow you’ve got a hundred of them and you’re not throwing them away–and line your cube with it.  After lining, you push the Popsicle sticks into the groove that once held the lid of the cube keeping the chocolate fresh.  The sticks make a press fit–and that’s the ticket to creating a wonderful self-locking-in-place drip edge that you can wipe a paint or varnish brush against as you work.  You’ll feel really clever that you found a purpose for your Trader Joe’s cubes, Popsicle sticks, and those non-zipping plastic bags that you really have no other use for but can’t seem to throw away.

At the end of the day, you let your cube sit so the varnish hardens in the plastic baggie.  In the morning, your Popsicle sticks will have a dry layer of varnish on them so you’ll remove them, replace the baggie with a clean one, push the sticks back in place on top and put your new varnish in your cube for the next day’s work.  Believe it or not, you can do this for days–or weeks in my case–as you work your way around the boat putting on your layers and layers of varnish.  No real cleaning required, either. If you’re really good, you only use one or two of your cubes and 4 to 8 Popsicle sticks.  If you’re a little messy, you might go through twice or thrice the quantity.  If you’re careless and you’ve been eating a lot of chocolate and lime-bars, well, it’s not that big of a deal to go through many, many more.  The baggie is the key to it all though.  A daily baggie keeps everything clean.  During my varnish-fest, I usually don’t clean my brushes but instead I store daily in a container of turpentine.  At the end of the -fest, I can do a cleanup of it or if I’ve been using an inexpensive chip-brush, I can throw it out. For painting, I tend to clean it or throw it out daily.

masts in the sky

The Power of Raspberry Pi–MythTV tweaks and techniques

This post continues my previous ramblings about using the Raspberry Pi aboard the boat.  To start this story at the very beginning, go to this post. To go to the previous post in this series, go here.

Screenshot of MythWeb running on Raspberry Pi 2

Now to discuss some lessons we have learned about using our RPI-2 with MythTV aboard Schooner Mahdee to record over-the-air TV broadcasts for later viewing: Why record when so much is available instantly over the Internet?  Four reasons:

  • we are often anchored where Internet access is unavailable, or the speed is too slow to stream video;
  • we pay for high speed (4G) access per gigabyte;
  • broadcast HDTV provides an effectively free source of additional bandwidth and the HDTV programming is often many times much higher resolution than via Internet streaming;
  • those shows can be saved on a hard drive for later viewing anywhere and anytime.

Stunningly beautiful full 1080 HDTV programming is often broadcast and can be saved for later viewing on a big vibrant HD computer monitor–even in places with no Internet at all.  Those very high resolution shows consume around 5GB per hour.  If using our 4G hotspot, at that rate, our entire monthly Internet bandwidth for work and pleasure is equivalent to a couple of HDTV movies.  By comparison, in some locations, we can record HDTV shows around the clock for free–an incredible deal!  In practice, each 24 hours of saved H-264 encoded HDTV recordings exceeds our total Internet bandwidth usage for the entire month. Our only cost is for the hard drives and each $150 hard drive can save thousands of shows and take up less space on the boat than a small paperback novel.  So, even when we could stream videos over the Internet, we rarely do.

Since we obviously travel a lot, our settings for MythTV are not set and forget–in contrast to more stationary users.  We use Antenna Web in each new location to determine where HDTV transmitters are relative to us and how well we can expect to receive different stations.  We have both an omni-directional and a directional gain antenna to choose from.  Spinning around on a single anchor makes the directional antenna unusable, but if the boat is fixed in orientation with multiple anchors or shore-tie, we can use it to increase reception of more distant HDTV stations.  Sometimes we can get great reception with the antenna below decks in a stealth mode.  For more challenging stations, reception may require an antenna be raised on a flag halyard–not so stealthy.

We have an inexpensive account at Schedules Direct which interfaces very well with MythTV.  With an Internet connection, we generally upload new schedule data every day or two.  There is limited (just the next 12 hours) program schedule data provided for free by the stations themselves on the transmitter frequency using EIT, but scheduling works best with longer range data and Schedules Direct provides about two weeks of scheduling. That data also includes lists of actors and other credits as well as descriptive information which we retain with our recordings and in a separate custom Ruby-on-Rails (RoR) web interface and database.

Schedules Direct also allows us to have four different locations in our profile.  Thus, we have one for each major city area we typically visit.  In those profiles, we can remove stations we do not want–such as those without English language audio–and our custom settings will persist until our next visit to that area.  I am constantly amazed at the number of over-the-air broadcast stations we can receive even when we are far from a metropolitan area.

With our large MythTV database of over 10,000 previously recorded shows, nearly 100 channels of available broadcast programs in many locations, and large number of rules and priorities about what we want to record, it can take several minutes after starting the MythTV back-end for it to figure out what to record. During that time, the MythTV front-end and MythWeb browser interface running on the RPI-2 will will show no scheduled recordings. Whenever possible, I use the command-line mythtv-status to see what is in the recording queue rather than running the more resource-intensive front-end. Even mythtv-status can take several minutes to complete and will show that nothing will be recorded until all of the data has been parsed and prioritized by the MythTV back-end.  Loading new schedule data from Schedules Direct can take nearly 20 minutes to process on our–admittedly overloaded–RPI-2. Sort of like sailing tack to tack to get to one’s ultimate destination, patience is required and one can not expect a newly added show to be put into the recording queue right away. I plan for the RPI-2 to take up to five minutes before a new recording is reflected in the queue.

With an Internet connection, MythTV gets program meta data for each recording so that we have images of cover art–which makes the front-end display nicer.  MythTV can also flag commercials so that they can be easily skipped during replay or even removed from the file entirely.  Commercial detection is very resource intensive, so we set MythTV on the RPI-2 to not do any commercial detection on the recordings. With this setup, the RPI-2 is also very useful as a desktop computer for me to browse the Internet using Firefox/Iceweasel, read and write email and other miscellaneous things all while displaying current weather data and monitoring anchor holding.

One glitch that I have encountered is that the MythTV startup script does not always work in Debian Jessie due to incompatibility with SystemD. The symptom is that the startup script completes with no errors, but the back-end is not running–starting and restarting MythTV using has no effect. The problem seems to be related to the init-functions command. Adding the following just before that call in /etc/init.d/mythtv-backend as follows helped:

_SYSTEMCTL_SKIP_REDIRECT=true
. /lib/lsb/init-functions

Then that fix failed so I am now manually starting MythTV using the old InitV command:

/etc/init.d/mythtv-backend start

It is also good to ensure that MythTV is not running before starting it and to make sure there is no file named /var/run/mythtv/mythbackend.pid. First kill hung processes and then check for the pid file and delete it if necessary before staring MythTV using the above command. Since I rarely reboot the RPI-2, manually starting MythTV works fine and the InitV command is trouble free.

Another glitch is that the HD HomeRun recordings sometimes fail leaving MythTV thinking the recording is still happening. After upgrading the HomeRun to the latest firmware, this situation happens less often. Still, every few days I need to stop MythTV and wait for all the threads to be killed and then restart MythTV.

Next, I will cover some system-wide optimizations that we have made that make MythTV more reliable given the highly loaded RPI2 we run it on.

The Power of Raspberry Pi–rethinking and restructuring to do even more with less

To start this story at the very beginning, go to this post. To go to the previous post in this series, go here. As it may be clear from the discussion so far, I have a tendency to increasingly add more requirements and functionality to my Raspberry Pi (and/or the newer version 2 RPI-2) computer until it cries “uncle”–or more often than not, just quietly dies under the extreme load. This post is about adding more functionality, but by being smarter, avoiding the dying part–at least for now.

myth tv running on raspberry pi
Every traditional boatwright needs to watch the Woodwright’s Shop for inspiration.

One of our luxurious activities when paying to be at a marina with shore power is to run my Shuttle small-form-factor (SFF) computer with its Intel i7 CPU and lots of RAM and lots of storage space. When it is running, it records over-the-air–using an antenna–HDTV movies and shows according to various rules we have programmed. Those shows are re-encoded by the Shuttle computer in a very efficient format to make the files smaller–1/3 to 1/5 original size–and then saved to a hard drive for later viewing–like when storm-bound in a remote bay somewhere in Alaska.

Our time in marinas is limited and the Shuttle requires too much power to run just for recording shows (producing non-shore power electricity is very expensive) and the movie recording program is way too demanding for a regular RPI. But now I thought maybe, just maybe, the new RPI-2 could record TV programs–of course I really mean do that in addition to all the other stuff the RPI-2 already does.

The program we use to record over-the-air shows is called MythTV. I have a love-hate relationship with MythTV, but we have been using it for about 10 years and it keeps track of every show ever recorded by us so that it doesn’t re-record something we already have on a hard disk or DVD or CD-ROM somewhere on Mahdee or in storage. The challenge for us is that the database for MythTV has a huge number of recordings (way over 10 thousand) to keep track of and the scheduler needs to sort through all of our rules (which are numerous and have evolved from our refinements over those same 10 years) and compare rule-matching scheduled showings to already recorded shows and determine which shows to actually record when so as to optimize the recordings. I had my doubts that even the RPI-2 would be capable–let alone doing that task while also doing the really important stuff like keeping track of the weather and how well the anchor is holding–after all, we do have to keep our priorities straight.

To make the RPI-2 able to record TV movies we had to make some changes.

1. We bought a network HDTV tuner (HD HomeRun Extend HDTC-2US) that has a built-in transcoder that re-encodes the movies in a more space-efficient format (H-264) on-the-fly. This removes the requirement for the RPI-2 to re-encode the recordings–which it couldn’t do anyway–and keeps the file sizes reasonable. In addition, H-264 is an open standard whereas the original inefficient proprietary format used in over-the-air transmissions requires one to buy a MPEG license before the RPI-2 can perform hardware decoding for viewing. So not only is the output of the HD HomeRun more space efficient, it also uses an open standard that doesn’t require the purchase of a license. The HD HomeRun even runs on 12V DC which is nice. So we installed a 60W regulated 12V DC power supply on Mahdee to use the HD HomeRun off a 12V DC battery.

2. The other change was to continually power up the Linksys Wifi router. The Linksys is also powered by 12V DC–so it can use the same newly installed regulated power supply as the HD HomeRun. Earlier, we tried to make the RPI be Mahdee’s Wifi access point in order to save the power required to run the Linksys. Running the Linksys offloads the Wifi access point functions but more importantly, also provides a needed Ethernet hub. The hub makes is possible for the HD HomeRun tuner to be available to the RPI-2, as well as to my Shuttle computer, all over fast Ethernet rather than Wifi. Further, we decided that we could also keep running the old RPI and use it via Ethernet to offload some functions from the new RPI-2–such as internet gateway, firewall, GPS server, network time server using GPS, secondary/backup anchor position alarm, Scrabble game server (oh–didn’t I mention that requirement), as well as that coveted contact and calendar schedule web server.

The net result is that, even though we now have two Raspberry Pi’s running (an RPI and an RPI-2) along with a network TV tuner and a Linksys router (the latter two alone adding 24 amp-hours a day to our afloat battery usage), our electric power usage is less than half of what it was at the dock with the Shuttle computer running. We are now getting recordings and a practical, fun to use computer that is available 24-7 even while at anchor. All that while logging weather and boat data and monitoring that important data with alarms to keep us safe. The RPI-2 has been exceptionally reliable with our previous and current up-time exceeding three weeks since the last intentional reboot.

When passage making, we can turn off the network TV tuner, Linksys router and the RPI to reduce power usage without loosing any important functionality–e.g. don’t really need our contact server in the middle of the ocean. And with no TV tuner, we can turn off MythTV and have plenty of CPU capability on the RPI-2 to run the OpenCPN chart plotter which can use either the weather/boat data pseudo serial port on the RPI-2 for GPS data or the GPS data on the RPI if it hasn’t been secured to save power. With this nice flexible and stable setup, I have to keep telling myself not to add anything new. Unfortunately, I know that it is only a matter of time before I come up with new ideas of things/tasks/programs to add to the RPI-2. With any luck, a new more capable RPI-3 will come out before I completely overload the RPI-2. Right now, however, I am really happy with both my RPI and RPI-2.  Next I will cover some tips for running MythTV on the RPI-2 without impacting all the other stuff the RPI-2 needs to do.

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