Archive for the ‘Miscellaneous’ Category

Finding a Picture That I Took Used on eBay

Sunday, January 6th, 2013

It is a bit surprising to follow a link from an eBay saved search and find a picture that I took.

Liebert UPS battery cable

The original is in this post from 2011.

I have no CC notices posted for the whole site (though I’d be happy to); but of course the Berne Convention provides for automatic copyright upon creation and publication of a work, so this is a blatant copyright violation.

Regardless, why is an eBay seller with only 110 feedbacks (vs one who does business on a scale of 110,000) too lazy to take their own picture of what they claim to have for sale?

72G or Larger SCSI-2 Fast/Wide Hard Drives?

Monday, November 26th, 2012

Anyone know where to find new, large-capacity SCSI-2 fast/wide hard drives? A computer I supported at a hospital a long time ago has a failing hard drive and I’m happy to assist with replacement but I’m not coming up with any sources for the hardware.

Hand-Soldering SOIC

Monday, July 2nd, 2012

I wouldn’t want to do it for a living, but it’s an enjoyable diversion once in a while, particularly as a favor for a friend.

Breakout boards with SOIC

I aligned each chip’s pins by hand, clamped it to the board with a gator clamp (with heatshrinked jaws), soldered the far row of pins, rotated the board, and soldered the now-far row of pins.

Three rows I was able to do by blob-and-drag (heat the pins at the uphill end of the row, make a big solder blob, and drag it down the row at a pace slow enough to heat the pins but fast enough to keep the surface of the blob from oxidizing too badly, trusting surface tension to bring the blob with you and leave only a lovely solder fillet below each pin). Three rows I ended up doing slop-and-wick (get solder all over the place, then use “Size: Good” solder braid to remove solder bridges from between the pins, leaving a lovely solder fillet below each pin and evidence scorched flux everywhere).

I’d take recommendations on a good flux remover — preferably detailed recommendations indicating whether you have to scrub or just spray, how cleanly it washes off, etc. You can see that the rubbing alcohol I used leaves a bit of residue.

Liebert Battery

Saturday, May 28th, 2011

Just found this unpublished draft from October. I had received a GXTV2-48V battery expansion cabinet for my Liebert GXT2-2000RT120 UPS and wanted to see what was inside.

Liebert GX2-48VBATT battery cabinet interior

Eight sealed lead-acid batteries are bolted down and connected through a circuit breaker / switch to the two input/output jacks in parallel.

Liebert GXT2-CABLE48V1 UPS battery cable

The cable to daisy-chain the battery expansion cabinets to the UPS is … substantial.

installed

Installed in the basement server rack (bottom) and connected to the UPS. Sure wish I had a bezel for the battery cage.

Cleaned It. What Now?

Friday, January 28th, 2011

Rotary crank telephone, dirty

People bring me the most wonderful things!

Rotary crank telephone, cleaned

Anyone have a favorite plastic polish?

Old telephone handset

I suppose I should build a VoIP phone system and get an analog terminal adapter, eh?

Does Used Tinnit Ever Work?

Friday, January 21st, 2011

The board being too long for my Pyrex dish and the overlap in the middle notwithstanding, this dull, mottled finish is typical of what I get every time I use TInnit other than the day I mix it.

PC board after tinning in used Tinnit

The precipitate never re-dissolves; and I’m guessing that the salts sitting directly on the board are what cause the mottling.

I find this curious, as I mixed this batch only two weeks ago, when it worked noticeably better than this … although now that I mention it, I think even then it produced duller results than it has in the past. Perhaps I exceeded the shelf life of the unopened package, so perhaps I’m being unduly hard on the Tinnit; but I’ve had the same problem before.

PC board after tinning in Tinnit and wet-sanding

I’ve been having good luck lately with scouring pads to shine up the boards; but tonight I had to resort to wet-sanding. Turned out fairly well.

No, that’s not how I typically lay out circuit boards.

Yes, I’ll be posting a lot more about what I’ve been doing for the last month as soon as Steve and I get his sculpture delivered to the gallery before 17:00 tomorrow.

Thomas Jefferson on Open-Source

Wednesday, December 8th, 2010

Why have I never before seen this quote, cited (as I find on Google) by a wide variety of highly reputed maker-friendly organizations?

He who receives an idea from me, receives instruction himself without lessening mine; as he who lights his taper at mine, receives light without darkening me.

Found in an interview with Sanjoy Mahajan, author of Street-Fighting Mathematics: The Art of Educated Guessing and Opportunistic Problem Solving, on the Freakonomics blog.

Visiting San Diego

Thursday, October 14th, 2010

I’ve been in Anaheim, California for a conference this week, and I had the happy opportunity over the weekend to drive down to San Diego and meet in real life a couple of long-time blog friends, Scott and Ben.

Keith's Restaurant sign

I knew I was in the right place as soon as I looked out my hotel window.

Scott Smith's laser cutter frame

Scott is building a copy of bdring’s DIY laser cutter, which looks fantastic. Over the weekend Scott was assembling the sleds that transport the mirror over the workpiece. It’s a very nice design — everything is modular and everything is adjustable.

Fly-milled delrin and aluminum

Scott and his machining mentor Peter generously demonstrated milling techniques on Scott’s Sherline mill. Shown is a fly cutter that was just used to smooth the surface of delrin and aluminum blocks. Although it’s not mirror-shiny, I was impressed at how easy it is (with the right cutting and feed rates) to clean up a face. Peter also demonstrated the use of an edge-finder to precisely position a hole drilled into the edge of an acrylic plate for the laser cutter.

Scott Smith's CNC mill interface

Scott’s mill came CNC-ready with mounts for stepper motors on all of the axes. Scott designed and built his own interface between the PC’s parallel port and the stepper controls, adding indicator lights and the all-important stop button.

Lemons on tree

California is full of things I’ve never seen before, like lemons on trees

Ben Wynne soldering an EasyBright

and people other than me

Scott Smith soldering an EasyBright

soldering together EasyBrights. I don’t have the microscope, though, so I don’t have to make the squinty face.

Ben Wynne's RepRap Mendel

Scott and Ben have both been interested in my progress (and lack of usable results) on my MakerBot CupCake and Ben had just finished assembling a RepRap Mendel when I arrived. It’s much more interesting in person than any picture or video I’ve seen has captured. Compared to the CupCake, it’s incredibly smooth, quiet, precise, and easy to calibrate. On day two, Ben was already churning out prints I envied.

Between Scott’s mill, Ben’s RepRap, and Scott’s laser cutter, they’re set to prototype just about anything. I did suggest that Scott should build a water-jet cutter next, but he wasn’t having any of that. I may need some time to warm him up to the idea.

Project boxes at Fry's Electronics

We paid a visit to Fry’s Electronics, a legendary California electronics components and computer retailer. Although they’ve transformed into primarily a big-box electronics store, I was still impressed with their hobbyist / components section, including a larger variety of project boxes than I’d seen in one place and a good selection of components, including SMT passives, right there on the rack for the buying.

Min Smith playing guqin

Back at Scott’s house, his wife Min was practicing her guqin, a Chinese instrument you may remember from a Jet Li movie. Having been raised listening almost exclusively to western music (“We have both kinds!” — no, not that western music), I found its tuning even more unfamiliar than that of the guitar — it’s not tuned in regular intervals.

Sunset over the Pacific

To top it all off, we had time to wander down to the beach for a California sunset. Thanks, Scott, for an excellent visit with good electronics, great food, and local sights!

How You Know the World Has Changed

Thursday, September 16th, 2010

On my way to work, I drove past a maybe 12-year-old girl riding her bicycle to school on the sidewalk, kind of wobbling along unsteadily like she’s not very good on a bike yet, helmet strapped on her head and pink backpack on her back, TALKING ON HER CELL PHONE.

Folder Structure Standardization and Unison for File Synchronization

Tuesday, February 16th, 2010

We’re smart, electronics- and computer-savvy folks, right? So why is it that when I’m trying to figure out which of my computers a particular EAGLE project is on, I have to envision where I was sitting:

  • couch or kitchen == iBook or MacBook
  • home office == workstation
  • work is unlikely but == work computer

and about how long ago it was:

  • more than a year == iBook
  • less == MacBook

? Shouldn’t all of my files be available to me wherever I am? Why should I have to guess and look around and always have them in the wrong place?

Oh, sure, when I upgraded from the iBook to the MacBook, I could have used Migration Assistant to copy everything over; but it seemed like a great time to declutter, organize, and start fresh. And it was, until I didn’t get around to the organizing part and needed EAGLE files I hadn’t brought over yet. Like, now.

I’ve been home sick from work today yesterday and today, and during the parts that I was awake I got files synced across my different platforms. I haven’t been playing sick to get a chance to sync up my computers — whatever I have is making me sniffle, speak about an octave lower than normal, drink gallons of orange juice, and listen to Madonna CDs. You don’t want what I have, and neither do the people I work with.

Unison Background

For a long time, I’ve been intending to install Unison for syncing my electronics project files (entire hierarchies, actually) across the different computers I use. Now I’ve actually done it.

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