Archive for the ‘Miscellaneous’ Category

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.


Need a Name for a New Site Feature

Sunday, January 31st, 2010

I have a lot of old electronics equipment that I thought I wanted to save at the time I got it but is of no particular use to me. I’d love to find new homes for it; some I’d give away for the cost of shipping and some I’d take offers.

I’m thinking about setting up a new area on my web server to post pictures of and information about things I have available, and I’d like a good name for it so I can link it as and, but I don’t know what that name should be.

I’d love to call it, but it won’t all be quite free. I don’t want to call it “store” because I’m hoping to turn a couple of my projects into kits soon and I’d like to reserve that name for information about the kits.

The best I’ve come up with so far is “fleamarket,” and I’m not wild about that.

Suggestions welcome. Free junk for the “winner.” :-)

SparkFun Tour

Sunday, August 23rd, 2009

At the end of July, I was traveling in the Boulder area and had the privilege of getting a tour of the SparkFun headquarters. I got my first Arduino from them; and although I’m not a terribly frequent shopper, I follow their blog assiduously and I love what they do, so it was a pretty thrilling experience.

SparkFun headquarters, exterior

SparkFun posts a lot of pictures on their site and they’re not shy about showing off their facility, but the online photos don’t give quite the same perspective on their operation that an outsider gets when coming through for the first time. They told me there was nothing I couldn’t photograph and post, so I wanted to share a bit from my tour.


I Bought a Bus

Tuesday, June 2nd, 2009

For years, I’ve been enthralled with the idea of buying an old schoolbus, ripping out the seats, and converting it approximately into an RV. While in college, I thought it should have a B/W darkroom and that I should cross the country taking and printing photos; but today film is out of fashion and I’d rather it have an electronics laboratory (that’s “la-BOHR-a-tree”).

Converted schoolbus, left front

My dream appears to be taking shape in reality. Last week I won an auction for a half-converted former schoolbus previously owned by a university athletics fan and used as a tailgate bus. It already has the seats removed, potable and waste water tanks plumbed, and many other interesting “features.”

I’ve started a new schoolbus conversion blog to describe the project. I’ll cross-post to the electronics blog only when work pertains to electronics; so if you’re interested in the schoolbus conversion in general, you should subscribe to that blog separately.

Posts will be relatively infrequent as I expect the projects to be larger and take longer.

eBay “Misprinted” a Coupon and Won’t Honor Terms

Tuesday, November 18th, 2008

Not electronics; but it’s chic these days to dis on eBay, and hey, it’s my blog.

Just won an auction last night for another SAE A502 amp for $200 + $40 shipping (and that shipping cost is legit — every A502 I’ve bought has cost the same amount to ship), so it seemed like a perfect time to use my 10% off + free shipping coupon.

eBay coupon for 10% off plus free shipping

Except when I entered the coupon code on the checkout page, it didn’t take off the shipping. A close examination of the fine print shows that it doesn’t say anything about free shipping — but there it is in big letters at the top of the page!


Transcript of my live eBay chat:

Initial Question/Comment: Other

08:52:47 SystemSystem
Thank you for contacting eBay Live Help!

08:52:47 SystemSystem
Please hold for the next available Live Help Agent.

08:53:32 SystemSystem
Mark L. has joined this session!

08:53:32 SystemSystem
Connected with Mark L.

08:53:32 AgentMark L.
Hello, thanks for waiting and welcome to eBay Live Help! My name is Mark. How may I help you?

08:54:24 Customerneufeld****
Hi! I got a message in my inbox that says “10% off coupon enclosed + free shipping.” I tried using the coupon last night to pay for an item I won, and it took 10% off the purchase price, but it didn’t adjust for free shipping. Could you clarify how that’s supposed to work?

08:54:42 AgentMark L.
Sure, I will help you with that.

08:55:32 AgentMark L.
Are you referring to the coupon that states 10% off on shipping from the purchase price?

08:56:30 Customerneufeld****
Well, I’m not sure how to describe it, other than to type in everything that’s on the coupon and in the text below. Is there any way you can look at what’s in my inbox?

08:57:18 Customerneufeld****
The graphical part of the coupon says “Free shipping on gifts they want,” then down below it says 10% off the purchase price of a single item. The coupon code is CHOLIDAYNOV2008.

08:57:48 AgentMark L.
I am sorry but that it was a mis-print on the coupon. We will be sending a new message to you that will state that the coupon had a mis-print and there was no discount on the shipping.

08:58:49 Customerneufeld****
That sounds an awful lot like false advertising to me — you can retroactively change something like that and not get in trouble?

08:59:07 AgentMark L.
I do understand that this can be upsetting.

08:59:42 Customerneufeld****
I’m just curious.

09:00:13 AgentMark L.
Have you already paid for the item?

09:00:17 Customerneufeld****
I mean, eBay is the 800-lb gorilla of online sales, and I recognize that I alone can’t change what you decided to do. But I’m honestly curious if that doesn’t fall under false advertising law.

09:00:43 Customerneufeld****
Haven’t paid yet — I contacted the seller and said I had a question about how to use a coupon, and I’d be back in touch with him today. He said no problem.

09:00:57 AgentMark L.
I am very sorry that you have to go through this.

09:01:13 AgentMark L.
However, the coupon will not be applied to get the free shipping on the item.

Well, that’s what I needed to know.

09:02:00 AgentMark L.
There is no need to worry about. We send several coupons on a random basis and I am confident that you will receive anther one so that you can enjoy the benefits of the coupon for your next purchase.

Obviously if eBay makes up it’s mind that it’s going to do something — legal or not — it takes more than one person to get them to change their mind. But at least I can have a little fun with the agent along the way.

Radio and Video Stuff and Projects in Progress from Slim

Sunday, November 16th, 2008

Last weekend, Lawrence and I went to Pittsburg to help Maeve clean almost the last of Slim’s stuff out the garage. Here are some of the first interesting items from the vanload we brought back. Some of this I’m keeping; some I’d love to place in a good home.

SWR and Power Meter

This is going to Cort.

Comet CD-270D SWR & Power Meter, front

Comet CD-270D SWR & Power Meter, rear

He writes:

I’d like the Comet SWR/Power meter… Yes, I have a MUCH MUCH better one now… But that was the one Slim and I did ALL of the early repeater stuff with. There’s a lot of sentimental value attached to it. I was having a HELL of a time trying to get reasonable readings. He showed up with that one day and it made life so much easier. It was one of those “gold standard” items for us for a number of years.


Don’t know what kind, but that’s an F connector on the bottom. Yours if you want it — any offer that includes shipping cost will be accepted.


TrunkLine Millenium Active Headend Combiner 95-AHC16

This combiner takes CATV signals that are already RF modulated and merges them onto a single feed. I believe this had never even been opened until I took these pics. Available claimed.

TrunkLine Millenium 95-AHC16 active headend combiner in box

TrunkLine Millenium 95-AHC16 active headend combiner, front

TrunkLine Millenium 95-AHC16 active headend combiner, upper rear

Datavideo Timebase Corrector

A card to go in a PC — as far as I can tell not even connecting to the bus for anything but power — to stabilize video sync before capture. By my estimation, a relic of bygone days, and available upon request claimed.

datavideo timebase corrector

Vidicon Tubes

Although I’d never actually seen them before, I recognized these pretty quickly as videocamera imaging tubes, and the labelling identifies them as Vidicon.

Box of Vidicon camera tubes

RCA 7735B Vidicon camera tube, side

RCA 7735B Vidicon camera tube, front

Available if there’s any interest:

Qty Condition Description
2 apparently new in plastic case RCA 7735B
2 not visibly damaged RCA 7735B in GE box
1 visibly worn but not visibly damaged RCA K1008 in GE styrofoam claimed
2 unopened 2AP1 in soft paper
Probably a CRT — keeping
1 unopened “2AP5 BLUE” in soft paper
Probably a CRT — keeping
1 unopened WA0EDA (?) in soft paper
1 “Was burnt in place (useable) [sic] Matsushita S4097 claimed
1 “Used / beam current varies” Hitachi 7735A used in box
1 face shattered RCA 7735A, loose
1 face edge cracked, something loose inside Ampex 4508, loose claimed

Speaker in Swivel-Mount Enclosure

Speaker in swivel-mount enclosure

Perfect prop for the next Brazil.

Slim’s Portable Powered Speaker

This is a cute little Slim-built powered speaker. That appears to be a PL-259 plug with the tip broken off on the front — I’m not sure what the logic was behind using that connector. I’m thinking I should replace the connector and hang this on the wall above the workbench.

Slim's portable powered speaker, front

Inside, a 9V battery clip and audio amp module.

Slim's portable powered speaker, interior

Glass Heating Plates

This looks like some kind of experiment. Electrically-heated glass plates, half assembled. Slim was very interested in optimizing PCB production; maybe this was a test for heating etchant? Maeve takes hot tea and was always looking for a way to keep the pot warm; maybe this was a test for a teapot pad?

Glass heating pad, front and back

Glass heating pad, backlit

HeathKit Programmable Wind Chimes

I just missed the HeathKit era and never had the opportunity to assemble one (although I have of course assembled other electronics from kits, just not HeathKit). Here’s an electronic “wind chime,” complete and completely unassembled. Wow.

HeathKit TD-1089 programmable wind chimes, unassembled

HeathKit TD-1089 programmable wind chimes assembly guide

I’m torn between the opportunity to finally build a HeathKit, and the desire to preserve this forever just as it is. :-)

Indicator Light Bezel

I love this! Wish I’d found more of them, but so far only the one. Er, two. Well, the one bezel that’s a two.

Lensed 2 bezel, front

Lensed 2 bezel, side

Lensed 2 bezel, lit

Edge-Lit Plexiglas Demo

Thursday, November 6th, 2008


Welcome, Make and Gizmodo readers! I didn’t expect this kind of attention; but you mention light sabers, I guess geeks like us are bound to get excited. :-)

This was meant to be a crude, quick proof-of-concept prototype, and at that it succeeded. I now have 500 white SMT LEDs on the way from Hong Kong; and when they arrive, they’ll each — grain of rice sized — get glued to the end of a piece of plexi, where they’ll be nearly invisible when off. It’s up to Lisa whether the connecting wires will be visible or minimal; and bless her heart, she says she wants to incorporate visible wires into this piece, so I don’t have to mess with 1000 hair-thin, enamel-coated wires.

Finally, this is only good for artistic purposes or accent lighting. As you may have noticed when shopping for LED light-bulb replacements, there’s very little out there even close to the brightness of incandescents. If you want to light a hallway as you walk through, I’d suggest Piranha (bright) or Luxeon (brighter) LEDs in the baseboards and an ultrasonic rangefinder at the end of the hallway to determine your position.

Edge-lit plexiglas strip in LED tester

I have the privilege of working with Lisa Rundstrom on an art installation for a show at the end of November. Lisa does amazing work with plastic (especially acrylic) and light (really, go look at her site), and we’re planning a cloud of 200+ hanging acrylic pieces, edge-lit with white LEDs, interacting with audience members.

If I don’t descend into gibbering madness from the impending deadline, the piece is going to be amazing. (If I do descend into gibbering madness, I expect that’ll be amazing too.)

Our art / technology / education collective has been meeting once a week in preparation for the show, and last night I built a little demo to give a rough idea of what controlled LEDs could look like.