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Drying out soaked electronics

June 4, 2007 7 comments

Yesterday I was working on a bicycle in extremely pleasant weather, using my small digital camera as a digital notetaker while disassembling a complex hub.  I went inside to send an email about it to my son, and whoosh! an Illinois downpour struck.  Water thundered down out of the sky, soaking everything in sight, including my camera.

This is the same camera that once fell off a ladder – I was using it to document an installation and climbed down to speak to someone.  Then I went to move the ladder, and it fell 8 feet to carpet, undamaged.

I used to repair cameras and knew the prognosis for a soaked camera was not good.  That the liquid was rainwater was a point in favor, because rainwater is usually not corrosive (depending on the proximity of coal-burning power-plants).  I once opened up a camera that had been dunked in seawater and suffice to say, sorry, no way.

I dried it off best I could, but the inner mechanism was full of water.  I needed some way to dry it out fast before the internal parts began to corrode.  What’s a steady source of heat?  I turned on my Rotel amplifier – it has a high bias voltage so it runs rather hot.  Left the camera on top of it overnight.

Put the battery back in this morning and darned if it didn’t fire right up!  But since I am apparently the kind of doofus who would pull a stunt like this, my next camera is going to be an Olympus Stylus 720SW.  It’s waterproof down to 10 feet.  And like my Dimage Xg (which is no longer manufactured but is a steal on eBay at around $100) is exceptionally shock-resistant.

Categories: Geeky, hardware

Minor victory through procrastination

April 5, 2007 1 comment

Digital projectors are funny beasts.  They get a video signal from a computer or other device, and display it on a small LCD screen behind the lens.  The screen is illuminated by a ferocious gas bulb, xenon, I think, which projects the image on a screen.  In operation, they get hot and always have cooling fans, air filters that need to be cleaned, etc.

We had one in a classroom that kept dropping the image to garish colors and static.  It was an intermittent problem, the hardest to diagnose, but we had it nailed down to the projector itself and not anywhere on the signal path.  I took the projector down off the ceiling and ran it on my desk, reproducing the problem about 1 cycle out of 10.  Sanyo issued an RMA (Returned Materials Authorization) and I shipped it to them for warranty repair.

Three days later they called back, leaving a message on my desk phone.  They “ran it for two days” and “couldn’t find any problem” but it “needed to be cleaned” for which they wanted to charge us. (“cleaning” consists of blowing out the projector with compressed air, by the way)

The “we plugged it in and the problem didn’t happen” school of diagnostics only pisses me off.  Obviously they didn’t cycle it enough times to reproduce the problem.  Admittedly it can be time-consuming, and diagnostics can be difficult.  I used to inspect circuit boards with a magnifying glass to find evidence of component heating, or gently touch IC chips with my fingertips while the board was live (got a few blisters that way over the years but a really hot chip without a heat sink is indicative).  Sometimes I’d cool components with compressed air (in the old days, we used freon) to spot thermal intermittent faults. I’d look for wobbly fans, clogged air filters, pinched wires, delaminated circuit traces, leaky caps, or cracked solder joints.  Seldom had to go as far as signal-tracing.  Finding the problem does take time.

Disgusted, I didn’t return the call right away.  I waited two days and called back.  Much shuffling of papers and querying of co-workers ensued.

“Oh, they tested it for two more days, and the picture went all green and full of static.  They traced it down to a faulty IC.  We’ve repaired it and cleaned it under warranty, and it’s on its way.”

Yeah!

Categories: Geeky, hardware

Apple computer review part one: hardware

March 24, 2007 18 comments

Update: My review of the operating system, OS-X, is up.

You know those magazine reviews that claim to review “Mac Vs. PC”?  The ones where they have a bunch of benchmark tests and comparable programs under “laboratory” conditions conducted by people who are stone-cold experts in both platforms?  This isn’t one of those reviews.  I’ve made my living repairing and supporting Windows™ computers for well over a decade and always hated Macintosh computers.  And I’ve struggled with Linux so the only useful thing about this review might be addressing; “Is there hope for platform migration?” (which is another way of phrasing “Can an old dog learn new tricks?”)

First I got a day-long briefing at Apple’s expense in their fabulous Chicago office on the something-somethingth floor of some big building there.  (My bad memory provides them with far more disclosure protection than the NDA I signed) They covered the basics of the OS-X interface, integration into Windows environments, and the iLife suite of goodies that comes with every Mac now.  And they promised to loan me a Mac – any model I wanted for a whole month. 

I’m a laptop person.  Sure, I have an office but I really think of my office as three pounds of carbon fibre composite and titanium that is my Thinkpad X40.  It goes everywhere I go and takes a pounding from my insane bicycle riding, when I’m not wearing the matte-finish keys to a high gloss.  So I chose the closest thing, a Macbook.

Hardware description:

Apple finally made a laptop that didn’t look like a Fisher-Price toy, and it’s about time.  The Macbook was full-sized (and about 7 lbs with the adaptor) with a big, gorgeous screen and a full-sized keyboard.  They even moved the keyboard locator dits to the same location as the PC, on the F and J keys.  (Apples used to have them on the D and K keys, I think, which drove me nuts.  Whenever I heard “Think different” I always wanted to add; “… just for the sake of being different”)

All the cable connections were on the left side of the Macbook.  This is fine unless you are left-handed or unless like me, you got used to using a mouse with your left hand when you broke your right shoulder, and never went back.  I would have appreciated at least a USB connection on the right side of the laptop. 

Farthest left in this picture is the power connector, a clever bit of which Apple makes a big deal.  It does not insert into the laptop, it just sticks onto the side with magnetic force.  That way, if someone trips on your power cord in a coffee shop, the connector just releases instead of pulling your pride and joy off onto the floor.  I like it a lot except for one thing; the magnet is so strong that I had trouble disconnecting it without pulling on the cord, which makes me uncomfortable.  I finally got to tilting the connector up or down to break the connection without damaging the cord, but most people will just yank the cord so you’ll see a lot of these break.  All because Apple didn’t put any gripping surface on the connector block.

Next is the RJ-45 Ethernet connector (gigabit speed! This puppy is future-ready.) I would have liked a little lip around the opening for tactile location. 

Then a digital video output.  This is fine, if you are one of the tiny minority of users who connect your laptop to a digital projector or monitor; the rest of us would prefer a plain old DB15 SVGA so we don’t have to carry around (and keep track of) a digital adapter dongle.  Many times I have had presenters come to our college toting a Macbook and ask; “You wouldn’t have an adapter, would you?  I left mine back at the hotel.”

Then a firewire, and a couple USB ports, and the mic and earphone ports.  Will someone please tell Steve Jobs that there’s a color-coding convention for those last two?  It’s green for earphone, red for microphone.

On the right-hand side of the Macbook is a skinny slot for CD’s and DVD’s.  Having no flimsy tray is a real plus – you just stick the disk into the slot like a car player.  Very nice, and although I wonder if it makes the drive vulnerable to dust, you can expect all laptops to start doing it this way soon.

Nowhere on the Macbook will you find a PCMCIA slot.  Apparently that’s passe’ due to accessories now coming with USB connectors.  Expect PC notebooks to stop having them soon. Rest In Peace, PCMCIA.

Nothing on the front of the Macbook but featureless plastic.  On the back is the screen hinges and speaker grilles.  That seems odd until you realize the clever engineers at Apple are bouncing the sound off the screen itself.  The sound itself is surprisingly good though obviously you’ll want to use headphones if you’re doing serious media work.

By the way, the screen won’t open all the way flat – Apple has decided for you what the maximum opening should be.  Great, unless you like to work in unconventional positions for some reason, plus it’s an invitation to a broken hinge.  Think different, Steve.

The keyboard keys are perfectly flat rectangles.  They have a fairly noticeable collapse force for tactile “make” feedback but the flat surface is annoying.  I prefer dished keys.  No doubt Apple will have some long-winded explanation of why flat keys are better but I didn’t find it suitable for long periods of typing.

The front edge of the open laptop is an uncomfortably sharp edge.  Granted my hands are a bit sensitive but I found it annoying.  If it were my laptop, I’d be rounding off the plastic with a small block plane.

There are no hardware controls for sound, and the power button is difficult to detect by touch alone. Tactile cues, Steve, tactile cues!

This is a recurring theme in all the Apple hardware I looked at; ergonomics is consistently sacrificed to visual esthetics.  I can imagine the designers at Apple standing this book up on edge like a black monolith and gathering around it holding hands and humming the theme from 2001, A Space Odyssey

As with all laptops, the built-in pointing device is pretty useless.  I tried it and my hands were in serious pain in nothing flat.  You will probably want to use an external optical mouse as I wound up doing.  (Enter tirade about Apple’s refusal to make real two-button mice here.  Yes, I know their new mouse has ESP or something but there’s no tactile feedback from spooky sensors.  Just give me a damn button I can click, OK Steve?)

The screen is just sensational.  it is bright and crisp without being garish and was a joy to use for editing photographs.  It did a great job of presenting text clearly so reading long documents was easy.

With the laptop closed, there are few clues to which long edge is the hinge, and which edge opens.  It was like an overly symmetrical door that you keep running into because there’s no push-plate.  I finally put a piece of electrical tape along the hinge side on top to provide a tactile cue.  If you turn it round so the Apple logo appears upside-down to you before opening it, that is the correct orientation.

There is no lid latch; instead the lid is held closed by a pair of strong embedded magnets.  Here you see a small pair of pliers held up on the corner of the screen by the magnetic force.  These magnets are nifty unless you work in an industrial setting where there might be iron filings; admittedly that would not be a common problem.  (I prefer the lid-lip on my X-40.  When the lid is closed, it becomes one mechanical piece with the base so external force cannot act upon the latch). 

The body of the laptop is polycarbonate plastic. This is really good stuff (think of those tumblers they use in restaurants) but not as rigid as I’d like.  Granted I’m used to one of the most durable laptops on the market but I’d like to see Apple make an enhanced-durability model.  Aside from that observation, the quality of the hardware is absolutely first-rate and that extends to all the Apple hardware I’ve looked at.  There are no accidental details on anything Apple makes, even if they didn’t have the foresight to hire me as a consultant. 

I didn’t measure the battery life but I did run it dry a few times and that almost never happens with my Thinkpad (for which I don’t even bother to carry an adapter). 

To some extent this is an operating-system observation, but speed-wise this puppy is fast on the Decrepit-speed benchmark.  Subjectively it is way ahead of the Windows-running core-duo laptops I have used.  It also boots up faster, and goes in-and-out of sleep mode, faster than any Windows laptop I have used including core-duo.  If you don’t like waiting around for your hardware, you probably will like the Macbook.

The Macbook comes with a little remote control (which closely resembles an iPod Shuffle)  for giving presentations.  Neato.

The wireless connection is also worthy of note, but again that is an operating-system thing because the most important thing about it is the interface (it’s the same protocol we all know). 

Well I’m out of time, I’ve got to go to the gym.  There’s lots of interesting stuff to say about OS-X, the new Apple operating system.  I’ll put that in my next post, which should be tomorrow evening.  Tonight it’s Monty Python and the Holy Grail at the local theater.

Categories: Geeky, hardware

Mac vs PC… the coffee shop poll

March 4, 2007 2 comments

I am sitting in a coffee shop that is way hipper than I will ever be, and when i got up to refill my POCoC (plain old cup of coffee) I looked around at the laptops.  There were ten, of which eight were Apples. 

What it means, I don’t know.  Tomorrow is the last day for this loaner MacBook that I have been carrying around, and then I will begin to write my 3-way comparison.  But at least in this coffee shop, the smart-aleck Mac guy is kicking the PC guy’s ass.

Categories: Geeky, hardware

Mac on loan, part one

January 26, 2007 9 comments


I have a MacBook on loan from Apple Computer; here it is beside my ThinkPad X40.  My first impressions: 1) Wireless networking easier to use than any laptop I have ever seen.  2) “Intuitive” means “whatever you are accustomed to using.”  It took me 15 minutes to figure out how to open a new tab in Safari, and I still can’t open a blank one. 3) The keyboard is very high quality but flat keys seem odd to me.  4) Despite quite sophisticated power management the battery life is nowhere near that of my X40.  4) The screen is fantastic.  5) Would it kill Apple to make a real right and left button for me to click on? 6) You have to use a dongle to hook up an external monitor. 7) Though a distinct improvement on earlier MacBooks, it doesn’t strike me as being that durable 8)  It enters and recovers from “sleep mode” very smoothly 9) It is really, really fast. 

In other news, I got SUSE Linux Enterprise Desktop (SLED) 10 installed on my ThinkPad X23.  My first impressions: 1) It is easy to use, 2) except for the wireless which I haven’t got working yet, 3) it comes with a TON of very well-designed software.  BTW I much prefer OpenOffice to MS Office.  3) The screen looks nicer than with Windows – SUSE apparently has some very good video drivers.  4) It is faster than Windows XP on the same machine.  And of course 5) it has a better command line than XP.  (I miss my programmable text editor, though.  Will have to find a *nix version of Notepad++  and hopefully an Apple version too)

So I have 3 operating systems for the next month.  I will definitely write a huge head-to-head comparison ‘round the beginning of March.

Categories: Geeky, hardware

Blue Screen Of Death

July 8, 2006 3 comments

After 11 years in computer support, I’m pretty familiar with the “Blue Screen Of Death”, or BSOD.  It can mean anything from “restart your computer and everything will be fine” to “Kiss your hard drive goodbye”.  So I wasn’t too thrilled yesterday afternoon to see it on my beloved IBM X40 laptop.  It had been a week since my last backup, and I had a half-completed project on it.

Windows wouldn’t boot, and it blue-screened at ‘mup.sys’ which can indicate trouble with a device driver.  I figured it was related to the USB external CD burner I’d connected earlier and that turned out to be the case.

It took a couple hours of command-line negotiation from an XP boot CD, but finally I saw the login screen again and all is well now.  Diagnostics all pass.  And you better believe I ran my SyncBack script on the “My Documents” folder!

Categories: Geeky, hardware

Not my brightest moment to be sure…

February 14, 2006 8 comments

Start with a cabinet full of electronic equipment.  Each piece of equipment puts out a certain amount of heat.  When the heat production balances the heat loss of the container (in this case, the cabinet) you have the operating temperature of the cabinet.  It’s a lot like a falling object; think of acceleration due to gravity as analogous to heat production, and air resistance as to heat loss; eventually they balance and you have terminal velocity, or operating temperature respectively.

If the operating temperature of the cabinet is higher than, say, eighty degrees

f

, you get increased equipment failures.  Manufacturers allow higher temperatures than that in their manuals but in my experience that’s about where you start seeing increased costs.  Since we have 28 of these cabinets, such costs can mount up. Now imagine you are me, and a little bit slow on the draw at times…

The rate of heat loss in the cabinet is a function of airflow and cabinet wall conduction.  You can’t do much about the latter but you can cut holes and install fans to improve the former.  So you take baseline measurements, and build a prototyping vent panel.  Experiment with different arrangements of fans and grilles to suppliment the cabinet’s built-in exhaust fan.  Record your results and when you hit the target temperature, develop your plan and order parts.

But it turns out you have trouble obtaining (at an acceptable price) the Nidec fans you prototyped with, so you try a different fan, one with slightly higher noise rating but easily available.  Too noisy.  You pore over fan specifications, trying to find the right combination of power, flow, noise level, price, and availability.

In all of this you’ve learned more about fans and airflow than you ever thought possible.  You’ve read white papers from fan manufacturers and struggled with the math of obstruction and pressure. 

Then you think; “Doh! Static pressure!”  The exhaust fans you’ve tested compete with the one already in the cabinet, creating a negative static pressure, or partial vacuum.  After all the reading you’ve done, you now realize this has a huge effect on the CFM, or ‘cubic feet per minute’, that a fan can move.

The original fan couldn’t do its job because of static pressure, and the prototype arrangement you rigged up only worked because it was powerful enough to be a brute force solution.  You’ve overlooked the obvious.  Could delivering free airflow in the right place – where the components themselves exhaust their heat – allow the existing cabinet fan to move more air and hit the target temperature?

You remove your prototyping fans and reinstall the panel with only the fan grilles in place.  In essence, you’ve invented “the hole”.

It works.  The resulting operating temperature was 1.5 degrees cooler than any other arrangement you’d tested.

Sometimes finding the right solution can make you feel like a complete idiot.

Categories: Geeky, hardware

Hard Drive Crash

October 17, 2005 20 comments

Update: scroll down to comment #10 for a better picture of this hard drive.  Feel free to copy and use the picture.

“Can you get my files back?”

“No.”

Inside your desktop computer is a data-storage device called a “hard drive”, so named because it stores data on a spinning aluminum platter (as contrasted with the mylar data-storage surface of a “floppy disk”).  These platters spin 60 times per second or faster and are mirror-shiny, perfectly flat as a telescope mirror is perfectly curved.  They are usually electroplated with a cobalt alloy because aluminum cannot record magnetic impulses.

The data is written onto the platter by a tiny electromagnet that floats a couple millionths of an inch above the platter at the end of a head actuator, which positions the head above the precise location of the magnetic imprints.  This electromagnet is called a “Read/Write head”.  Normally it never touches the platter when the drive is turning.

When drives fail, they usually make a clicking noise known as the “Click Of Death” as the drive controller (the circuit that steers the actuator arm) seeks but cannot find track zero.  Another failure mode is a “Drive Crash”, where the head literally crashes into the moving platter, grinding away the surface (and your data).

This drive made a horrible screeching noise in operation as the R/W head ground its way into the aluminum.  Usually the platter surface is intact except for the inner-most track (track “0”), but in this drive there was a bonus; the head kept seeking after the crash occurred, grinding up the whole surface of the disk.  The drive was full of aluminum powder.


Notes:

By the way, if you can get ahold of an old hard drive, take it apart.  They’re very interesting devices.  The platters are so perfect you can reflect a visible spot of sunlight a couple blocks away.  Hard drives contain the strongest magnets most people will ever see – usually a neodymium alloy with cobalt, iron, and/or samarium. (and strong enough to stick a magazine to your refrigerator).  The ring-shaped spacers between stacked platters are (like the platters themselves) machined to absurdly fine tolerances – for some reason it is inspiring to handle such precise parts.

Shown in this picture is the interior of a normal hard drive.  Upper-center is the data storage platter, which rotates around the main spindle.  Extending into the platter area from the lower right is the actuator arm.  At the upper tip of the arm is the read-write head.  At lower-right is the “voice-coil” portion of the actuator (where the super-strong magnets are located), which moves the arm around the actuator spindle to locate the read-write head on the platter surface.  Not shown is the drive motor and control circuit, as they are on the other side of the drive.

Categories: Geeky, hardware

“Old Paint” goes out to pasture, but he’ll be back

May 13, 2005 2 comments

The customer’s computer was a smoking hulk, burnt by lightning.  I found his hard drive, containing precious data, intact, and mounted it as a second drive in the new computer he purchased.  The rest of the computer, charred wires and all, we placed by the back door to be put in the dumpster.  After work that day, I put it in my car.  It was just perfect.  I think the year was 1998.

Everything but the sheet-metal case went right in the trash.  Combining a new power supply with scrap components from junk computers, and a PII/266 motherboard I’d bought from a customer who was upgrading to the new Intel PIII processor, I assembled one of innumerable “FrankenPuters” that I’ve built over the years.  This one was for me.

Fast-forward to May, 2005 – I’m still using the same pile of junk parts and it still works perfectly – but a little slowly.  Time for an upgrade.

I no longer work at a computer store, so my endless supply of junk parts has dried up.  I think I’ll buy actual, new parts this time… but I’m keeping the scorched metal box they all fit in.  It’s butt-ugly, and I kinda like it.

So I’m typing on a borrowed computer while “Frankie” is on my repair bench.  In few weeks I’ll have collected enough parts to put it back in service as a battered-looking, 8-year-old, “New” computer. 

  • PC Power & Cooling power supply

  • Asus motherboard
  • … and probably a dual-drive SATA RAID storage system, and a gig of RAM.
  • … and a Plextor DVD burner for data archiving
  • I really don’t care about video cards – if the motherboard doesn’t have it built-in, I’ll use one of my old Matrox Millennium 4mb PCI video cards.  They’re reliable, stable, compatible, and I don’t play video games.
  • I also don’t care about sound – if the motherboard doesn’t have it built-in, my PCI Sound Blaster will be fine.

The power supply is an under-appreciated component.  If you really want a reliable computer, you’ll pay extra for one that provides stable power over a wide range of utility power fluctuations. 

More details later but I’ll put ‘em below the “read-more” link ‘cuz heck, most people couldn’t give a rip about some geek building a computer.  Especially since I like to build for stability over performance – the “Hank Hill” of computers.

Categories: Geeky, hardware

Rescued wireless card

January 9, 2005 1 comment


A couple days ago we had an ice storm.  Everything got covered with a lovely jacket of ice, much to my delight because ice is pretty.  But there is a downside.

On the morning of the ice storm I slipped on the back steps and fell right on my ass.  It was more undignified than anything else and the worst part was MrsDOF had just warned me about the steps, oh, a minute before.  I picked myself up, dusted off, and went to work.

But my Lynksys/Cisco dual-band Wireless network card (shown here inserted in my rough-around-the-edges laptop) did not go to work with me.  It flew from my shoulder bag, landing next to the back steps where it acquired a thick coating of ice.  For three days I had no occasion to use it so I didn’t know it was missing.

Then today the ice began to melt and I found my card lying in a pool of ice water with water from the roof dripping right on it.  Darn!, I said, or words to that effect, and scooped up the card.  I sucked water out of it through the PCMCIA connection holes, dried it off with a towel, and warmed up the oven to about 110o F.  I turned off the oven, placed the card on the rack, and waited 4 hours.

It works fine.  Whew!

Categories: Geeky, hardware