MG in the mountains

June 21st, 2015 Comments off

The little MG Midget was struggling. The altitude and the climb appeared to be wreaking havoc with the 1970-vintage British four-banger up front. She’d be fine for a while, then suddenly she’d seem to be on her last legs. Then, without warning, everything would be fine again. And so it went, all the way up 11,300 ft Berthoud Pass.

Tyler and I were on our way from Denver to Glenwood Springs. We were competing in a “rallye” organized by the local MG Car Club. In a time-speed-distance rallye — yes, that’s how they spell it — teams follow a list of driving directions and attempt to hit checkpoints at precise times. Early or late arrivals at the checkpoints worsens one’s score.

Tyler had acquired his MG a couple months earlier. There seemed to be no better way to enjoy it than with many other like-minded individuals.

Tyler’s 1970 MG Midget

I think that everybody born before 1975 has an MG story. They had one, or their parents had one, or they knew somebody who had one. Always past tense — everybody owned one and nobody owns one. So it goes with sports cars; the same could probably be said about Corvettes.

The day had begun in a downpour. The remains of Hurricane Blanca were over Colorado, and the heavens were adding precipitously to what had already been a very wet June. In the years since the MG was built, the front seal on the convertible top had deteriorated. Or perhaps it had never worked, British automotive engineering being what it was. No matter. A quick stop and a roll of duct tape came to the rescue.

Unfortunately, there appeared to be no role for duct tape in solving our engine problems. Speculation abounded about why we appeared to be intermittently lacking one cylinder.

Was it the cooling system? That was the leading hypothesis for a while. Despite a supplemental electric cooling fan and having the cabin heat on high, the temperature gauge still read near the top of its surprisingly limited range.

Was it general engine malaise? The previous owner had had the engine rebuilt just a thousand miles earlier, so something like poor compression seemed unlikely.

Was it something to do with the altitude? The Midget was built before the era of fuel injection, and its carburetors had been tuned for the significantly lower Denver elevation, so that seemed plausible.

Then, there was what would become my favorite guess: a rather vague “something to do with the ignition system.” Although I couldn’t articulate my exact reasoning, it seemed like a problem where one cylinder appeared to spontaneously cut out and then spontaneously rejoin the party was likely to be electrical.

After an agonizing (yet beautiful) grind up the pass, the summit mercifully presented itself. We had crested the highest point of the trip. The duct tape was ripped off, the top was stowed, and we cruised down into Winter Park in classic style. The sun smiled on us.

Touring the Colorado countryside behind a rainbow of other old MGs

The rallye proceeded along its meandering route towards Glenwood Springs. The engine continued to be temperamental, but the old girl never stopped lugging us along.

We made it to our destination after about 270 miles of driving spread across eight hours. Our performance in the rallye had steadily improved, and by the later stages we were claiming errors of just a few tens of seconds. Our skin was sunburned, our legs were cramped, and our smiles were large.

The MG Rallye route from Denver to Glenwood Springs

 

Days later, safely back in Denver after a lower and more southerly return journey, Tyler figured out the cause of the problem: there was coolant in the distributor. At least one cylinder wasn’t getting spark.

The car’s performance in the face of that challenge was all the more impressive. The original 60 horsepower had been reduced by at least 25%, and yet she still managed to climb through the Rockies.

Like the Little Engine That Could, the MG made it. “I thought I could! I thought I could!”

 

Homeownership is the art of plumbing

November 13th, 2014 Comments off

I woke up this morning to find the sun shining and the world glistening white. As always, I let Sophie outside and back in, then I returned upstairs for a warm shower. I twisted the knob to hot on the shower. Instead of a glorious steamy spray of heat, my action was met only with a dribble of cold. There was no water pressure. I put on a robe and began to investigate.

Despite being only November, the temperature had dipped to -10 °F overnight. My immediate suspicion was that a pipe had frozen somewhere or a water main had burst. The problem with the idea about a pipe freezing was that none of my plumbing ran in exposed locations. While my water heater did reside in a closet attached to my garage, the door opened into the garage, and being a townhouse, the garage stayed relatively warm: 45 °F according to my IR thermometer. The closet, which also held my furnace, was about the same temperature.

A new possibility sprung to mind. What if the pipe leading from the main to my meter had frozen? That would have been a real pain, as it ran underneath my concrete driveway.

Perhaps the blockage was somewhere else in the house, maybe a poorly routed pipe running through an exterior wall. I started going through the various faucets in the house and turning on the hot water to no avail. Then I got to the kitchen sink, which unlike the other faucets had a single handle to mix both hot and cold. I pulled the handle, and a healthy stream of water came out. Curious, I moved the handle back and forth from cold to hot. Cold worked great. Hot worked not at all. I figured that something had clogged the hot water heater.

Back to the garage I went.

With a flashlight, I began inspecting the hot water heater and its pipework. I followed the hot-water outflow pipe up from the water heater and… right past the fresh-air intake for the furnace.

Cold air getting sucked past the water pipes

Cold air getting sucked past the water pipes

The furnace had been running a lot during the night, so it had been consuming a lot of air, so a lot of very cold outside air had been flowing into the closet. Since no hot water was flowing while I was sleeping, all of that cold air had cooled the hot water line below the freezing point. A quick check with the IR thermometer confirmed that a short section of the pipe was at 28 °F –just below freezing.

Crossing my fingers that the pipe had not been frozen severely enough or long enough to do any lasting damage, I decided to unthaw that section. First, I turned on several faucets to hot so that any water movement would draw hot water from the tank and warm the icy blockage. Next, I got out a space heater, set it to high, and pointed it at the pipe above my head. After about a minute, I started hearing the hiss of a small amount of water beginning to flow. Thirty seconds after that, there was a bang, the pipe shook, and the water flowed. No leaks.

Back at the faucets, the water was gushing forth, hot and plentiful. I smiled and took a gloriously warm shower.

Update: It turned out that there was a second vent pipe to the outside.  It’s visible as the large bent pipe in the background of the image above. The vent pipe that was causing me problems appears to have no specific purpose. I’m at a loss to explain it; it doesn’t appear on any furnace-installation diagrams that I’ve found. I could see how it might be useful if I were to install a high-efficiency furnace in the future, as those vent out walls instead of out a chimney, but that’s just speculation.

Update 2: Apparently, it’s not uncommon to have a second vent to the outside. I ended up solving my problem by adding foam insulation around the pipes and adding some semi-rigid material to deflect any incoming air away from the pipes.

Scotch

June 21st, 2014 1 comment

I was one of the rare holdouts in college who didn’t drink at all until he was 21.  When I started to drink, I decided to go top-shelf right from the start. The way I saw it, why should I slog through swill? I didn’t want to drink to get drunk; I wanted to drink to enjoy the taste of the drink.

I ran the numbers and found that if I drank only rarely, I could afford really good spirits. Thus, I had one of the fancier liquor collections in the fraternity house.

The liquor shelf in 2003 (partially Tyler’s). The three bottles in the center were about $100 each. Fancy for college — or now.

The problem with that approach wasn’t so much that I didn’t learn to appreciate the good stuff — I did — but rather that it was easy to skip over cheaper options that I might have liked even better.

Jump ahead 11 years to last night. My friend Andrew decided to hold a Scotch tasting. About ten of us showed up, each with a bottle or two — or three — in tow. We made an effort to obscure the labels of the bottles using bags and masking tape, numbered each bottle, and proceeded to try very (very!) wee drams of all 23 options.

First, the good news: nobody had snuck* in anything particularly foul. Yes, there was an Irish whiskey and a bourbon, but they were both of decent quality. It was really a matter of distinguishing between the inspired drams and the ones that could be dismissed with a shrug.

Here’s the complete list of what we tasted, in no particular order, but probably with a few spelling errors:

  1. Macallan 15
  2. Glenlivet 12
  3. Laphroaig 18
  4. Macallan 12
  5. Macallan Fine Oak 10
  6. Laphroaig 10
  7. Cutty Sark Blended
  8. Glenlivet 21
  9. Speyburn 10
  10. Auchentoshan Classic
  11. Glenfiddich Reserve Cask
  12. Balvenie 14
  13. Dalmore 15
  14. Breckenridge Bourbon
  15. Glenlivet 12 (again)
  16. Glenlivet 18
  17. Speyburn 10 (again)
  18. Silver Seal 16
  19. Cragganmore 12
  20. Dalwhinnie 15
  21. Finlaggan Old Reserve
  22. Lagavulin 16
  23. Tullamore Dew

There was lots of swirling and sniffing and sipping during the blind tasting. Our palates became increasingly fatigued. Nobody got drunk — the tasting pours were just a few milliliters each — but whether from the alcohol or the shared challenge, discussion flowed, punctuated by brief fits of laughter. The temperature rose around the dining room table thanks to the bodies of the tasters and the occasional curious wine drinkers. The room smelled vaguely of vanilla.

Finally, everybody had tried and rated every option. We unblinded the bottles one by one. We each had favorite horses.

The Glenlivet Scotches on hand

As we reported our scores for each bottle, it quickly became clear that we had different tastes. One man’s 5 (out of 10) was sometimes another man’s 9. Most polarizing were the Islay (pronounced eye-luh) Scotches, of which there were four. Some loved the peatiness. Others hated it and spent the next three drams complaining about how they still could taste nothing but smoke.

There were accidental duplicates in the running, present as unintentional consistency checks: both the Glenlivet 12 and the Speyburn 10 appeared twice. To the latter, I scored it 6 the first time and 7 on the second pass.  For the Glenlivet 12, it was 7 and then 9.  And that was the really big surprise: that second pass of the Glenlivet 12 was my highest-rated dram — but the bottle was one of the cheapest present.  With a range among the 23 options from $15 to $150, with a mean of $60, I had expected the higher-priced bottles to do better, but that was not the case.

For me, the more expensive bottles often tasted unduly flat, almost too smooth. I seemed to prefer the options with a bit more fire and spice to them.

It’s not clear why that was the case. I suspect that I burned up my palate early on while trying to suss out how much water to add to each pour. That, in turn, might have prevented me from tasting much at all in the “better” Scotches and having the harshness muted in those of not quite so high stature. Or it could have been fatigue, or it could have been the temperature of the bottles, or maybe the types of glasses that we used. Hard to say.

Or maybe, just maybe, I actually prefer the cheaper stuff. My college self would have liked to have known that.

* As an aside, “snuck” is an example of a recent evolution of the English language. The generally accepted past tense of “sneak” is “sneaked”, but that appears to be changing.

By the trail

June 1st, 2014 Comments off

I took my coffee and sat down at the picnic table a couple dozen steps from the trail. A 20-year-old birch tree shielded me from the morning sun. The pavement of the trail looked hot even at that early hour.

I appreciated what passes for silence in an urban park: only the distant din of traffic and the wind rustling through the leaves. A robin flew into my tree, sang a few  times, and flew off. An old man on a rusty department-store cruiser rode by, squeaking a response to the bird’s song.

Most of the cyclists on the trail were alone. There were exceptions. Couples on a slow helmet-less roll. Clubs of half a dozen whizzing past. A mother with her two young children, not far removed from trailing wheels. A father with his teenage son in matching Lycra kit, both on slick road bikes.

Some of the cyclists rode new carbon steeds. Others tooled around on whatever had been in their garages for the past couple of decades. Skill did not always match tools. A guy on a beat-up mountain bike flew by with a high cadence and a steady hand. A white-haired man with a paunch on a $10,000 Obrea tri bike strained along in the big chainring and little cassette cog.

Most riders gave a respectful “On your left!” to the pedestrians. Some were more inclined to treat their unmounted brethren as inconvenient pylons meant for passing as close as possible. Few dogs were on the trail; they played in the large green field behind me.

My coffee gone, I too set out on foot again.

How I introduced a 27-year-old computer to the web

December 12th, 2013 165 comments

Reviving an old computer is like restoring a classic car: there’s a thrill from bringing the ancient into the modern world. So it was with my first “real” computer, my Mac Plus, when I decided to bring it forward three decades and introduce it to the modern web.

My Macintosh Plus. Spoiler alert: here it is surfing Wikipedia.

It’s a lowly machine, my Mac. The specs pale in comparison to even my Kindle: 8 MHz CPU, 4 MB RAM, 50 MB hard drive, and 512 x 384 512 x 342 pixel black-and-white screen. My current desktop PC is on the order of 200,000 times faster — not even including the GPU. Still, that Mac Plus was where I cut my computing teeth as a child. It introduced me to C, hard drives, modems, and the internet.

Yes, in a certain sense, my Mac has already been on the internet, first via BBSes and later via Lynx through a dial-up shell sessions. (There’s nothing quite like erotic literature at 2400 bps when you’re 13 years old.) What it never did was run a TCP/IP stack of its own. It was always just a dumb terminal on the ‘net, never a full-fledged member.

How hard could it be to right that wrong?

Everything went smoothly at first. I had my mom ship the computer to me. It arrived in good condition, having been stored undisturbed in her basement since the mid-1990s. I plugged it and its external hard drive in, flipped the power switches, and watched the happy Mac glow to life on the tiny CRT. Sure, the hard drive gave a groan of protest when it first spun up, but that quieted down, and everything seemed stable with the data intact. At least for the first few minutes.

I was far down nostalgia lane playing a game of Glider when all of a sudden there was a loud *POP* and the smell of smoke. Panicked, I slammed the power switches off and pulled the plugs. It didn’t take much sniffing to find the source of the acrid odor: the external hard drive.  The stress of current after years of disuse had proved too much for one of the filter caps in the external drive’s power supply.

A cracked XY cap from the external hard drive’s power supply.

Fortunately, Digikey still sold those exact caps(!), and I’m handy with a soldering iron, so a few days later I was back in business. On to the networking!

To accomplish my goal, I needed a web browser, a TCP/IP stack, and some way to connect the Mac to my home network.

The web browser was relatively easy to find thanks to guys running long-forgotten FTP sites in the dusty corners of the internet. MacWeb 2.0 was both old enough to run on my Plus and new enough to render HTML and speak HTTP. Sort of. But we’ll get to that in a minute.

A whole 4 MB of RAM to play with! Good thing, because MacWeb required 2 MB.

Likewise, MacTCP existed in a version just barely able to run on System 7.0.  It didn’t support niceties like DHCP, but MacWeb was happy to use it, and it installed without problems, so there was the TCP/IP stack.

Getting the Mac physically hooked to the network was a bigger challenge. The Mac Plus didn’t have an Ethernet port, and things like WiFi were years from being invented when it was manufactured. A couple of companies made SCSI-to-Ethernet adapters about 15 years ago, but those were rare and expensive. I thought about the problem for a while, and it occurred to me that I could channel the early days again: I could use the serial port and PPP or SLIP to bridge to the outside world. Like dialup without the modem.

I set up my Raspberry Pi and ran some Cat-5 to it from the router.  Using a level shifter and a variety of old adapters, I managed to get a serial cable working between the Pi and the Mac. That took care of the hardware.

On the software side, I scrounged around and after several failed attempts found a PPP client that would run on the Plus and a super-simple PPP server called SLiRP for the Pi. Documentation for the combination of MacTCP, MacPPP, and SLiRP was, surprisingly, still available.  After a bit of tinkering with the configuration, I was able to get MacTCP to talk to MacPPP, MacPPP to talk to SLiRP, SLiRP to use the Ethernet connection, and so on through my router and out to the internet.  Since serial I/O on the Mac Plus was processor-intensive, throughput was limited to about 19 kbits/s, but 19 was a lot higher than 0.

A Raspberry Pi doing the heavy lifting for the computer that’s tens of thousands of times slower. The mess in the upper right is a level shifter, a null modem, a DB-9 to DB-25 adapter, and a serial cable.

Now, you might be wondering, “Wait, how did you get all of that abandonware on there in the first place?”  Good question! The Mac’s floppy drive was old enough to be fundamentally incompatible with PC drives, and I didn’t have any floppy drives in my modern computers anyway.

I tried going down the avenue of 100 MB ZIP disks, since ZIP drives were made in both USB and SCSI-1 versions. While I did manage to get the Mac to use the ZIP disks (and in fact switched to one for the primary boot drive), and even got my Windows PC reading the HFS formatted disks using some nifty tools, every attempt to move data from the PC to the Plus resulted in nothing but corrupted files on the Zip disk.

That left the serial port. I happened to have an old terminal emulator called Microphone already installed on the Mac. Microphone supported ZMODEM for file transfers, which you’re probably nodding your head about if you remember BBSes. Thus, to transfer files to the Mac, I SFTPed the questionably legal  files I needed from my PC onto the Raspberry Pi, plugged the Pi into the serial port, fired up Microphone on the Mac as a terminal, and launched Minicom on the Pi from the Mac. I nervously struck the keys to initiate a ZMODEM transfer from Minicom, selected the files, and hit enter. Minicom obliged, there was a BEEP! and a “Save incoming file?” dialog popped up on the Mac. Some un-binhexing later, I found myself running new software on my old Plus. Huzzah!

So, with the Raspberry Pi, MacTCP, and MacWeb all in place, it was time to surf the web! Right? Right?!

No. No surfing yet.

The MacWeb developers apparently took a look at the HTTP 1.0 spec, decided, “Who would ever need name-based virtual hosting?” and left out the feature that 99% of the sites on the modern web relied on. No support for virtual hostnames meant you got whatever you saw when you used the server’s IP address alone in the HTTP request, and for most sites, that was jack squat. Oh, and HTTPS, cookies, and CSS hadn’t been invented yet.

AAARGH!!!

I vented about the problems to Tyler, mentioned that I was in for a long stretch of coding to solve it, and was surprised when he whipped up a filtering proxy solution in about 20 minutes using Python, Requests, Flask, and Beautiful Soup.  (Update 12/16: here’s the code from Tyler.) The key to it all was that MacWeb would include the full URL, with the hostname, when making a proxy request.  Requests fetched the URL, stripped SSL and managed any cookies. BeautifulSoup stripped out things that MacWeb couldn’t understand, like CSS, Javascript, images, and DIVs. Flask pulled proxy duties, reading the request and sending the filtered result back to the Mac.

And that, friends, was sufficient to surf the web. It even looked surprisingly decent, almost like a mobile browser:

The Mac Plus Wikipedia page, as viewed on my Mac Plus

 

Hacker News as viewed by the Mac. Surprisingly readable given that MacWeb doesn’t support CSS

Sure, it was slow as hell, but it worked! Data loaded, pages rendered, and links were clickable. Even forms sort of worked.

Did I mention it was slow? It was slow. Soooo sloooow. Slow slow slow.  Like, minutes to read and render a page slow. Here’s a video showing how slow:

Whatever. The goal was simply to introduce the Mac to the web.

The meet-and-greet was successful.