Design Matters: Donald Norman

October 29th, 2008 by k8gu No comments »
Don Norman slide

Don Norman slide

Donald Norman spoke as a part of the Design Matters lecture series at UIUC on Tuesday. Here are a few notes from his talk.

The traditional design approach creates a one-to-one mapping between user(s) and a machine or service. However, it neglects the environment. One particularly egregious example is what Norman calls “machines that moon us.” For instance, computers are designed to look good from the user standpoint. However, if the back of the computer faces the customers or a glass wall, more people can see the mess of wires behind the computer than the well-designed part.

“Social signifiers” are trails that people leave behind. For instance, if we arrive at a subway station and the platform is full of people, it is likely that we are early for the next train. On the other hand, if we arrive and the platform is vacant, it is likely that we are late. Fascinating.

Organic processes tend to be asynchronous. Therefore, waiting is unavoidable in the real world. The goal is to make the wait interesting and engaging for the user. More on this at a later date.

In other news, two interesting Design Matters lectures are on the horizon. David Goldberg of the iFoundry initiative to modernize engineering education at UIUC is speaking on 4 November. The second one is actually someone I considered suggesting to the series but dismissed as a long shot…Nokia designer/ethnographer/anthropologist Jan Chipchase, whose fascinating blog is in my blogroll, is coming on 2 December!

» Read more: Design Matters: Donald Norman

Miscellaneous

October 27th, 2008 by k8gu No comments »

Just some miscellaneous news from happenings over the past month…first, the good news…

I passed the oral exam on Tuesday.  So, I’m officially ABD now.  There is a light at the end of the tunnel.

Nikon released the 50mm f/1.4G AF-S SWM prime lens at the end of September.  I guess I wasn’t paying close enough attention.  This is good news for D40 owners such as myself.  But, the price is almost as steep as the Sigma f/1.4 30mm and 50mm HSM lenses.  The 30mm lens would be a better all-around choice.  Perhaps Nikon will come out with something a little shorter by the time I’m ready to buy.  Until then, I’ll keep using the 50mm f/1.4 AF-D that I have on indefinite loan from work.

I managed to destroy the drivers in my recently-repaired TS-930S.  I considered swapping the drivers from my second radio into this one.  But, when I took that radio apart, I found that the capacitors had swollen.  So, I have parts on order to fix that.  UPS says they’ll be here today.  I requested a quote for the NTE236 replacement for the MRF-485 drivers.  They want almost as much for the NTE236 as RF Parts does for the MRF-485.  I think I’ll get the MRF-485s.

We had high winds yesterday (Sunday).  I lost the 80-, 40-, and 20-meter dipoles.  Sarah said, “Do you expect that (80-meter) antenna to last the winter?  It just broke in September.”  She’s right.  I’m not sure I’ll repair it if it breaks again.   It’s less than a week to the CW Sweepstakes and I only have one working radio (FT-840) and antennas for 10 and 15 meters.  The forecast calls for 65 and sunny on Thursday.  So, I’ll probably take the day to work on antennas.

» Read more: Miscellaneous

Trivial Gallery v1.0.0

October 24th, 2008 by k8gu No comments »

I wrote up a little Perl script that builds a gallery out of pictures organized in folders in order to host a gallery on my DSL router running OpenWRT.

Try it here

Get it here.

» Read more: Trivial Gallery v1.0.0

TS-930 update

October 9th, 2008 by k8gu No comments »
TS-930S AVR board

TS-930S AVR board

Thanks to KA5IPF and WE0H, who answered my query on the TS-930S reflector!  The oscillation was due to dried-out electrolytic capacitors on the AVR board and unhappy pass transistors on the heatsink in the back.  I bought 105 C capacitors instead of the 85 C ones that Kenwood used, plus bumped the voltage rating up to 63 V instead of 50 and 35.  Fortunately, I still had some leftover 2N5886’s, but I need to buy a replacement set of capacitors and pass transistors to have on hand in case the other radio fails.  I haven’t tested it in contest conditions, but all signs are good that we should be ok.  Maybe the NS tonight?

Have a Synton ARC (sorry about the ancient web site…we are going to fix it…sometime) meeting at 2:00 today.  Everybody else in the Club is building SoftRocks.  I’m bringing my IK4AUY preamp parts to start building.  Need to order some PL-259’s, probably today.  Yeah, and I need to finish writing my prelim exam document and presentation.  So much to do.  So little time.

» Read more: TS-930 update

The Decisive Moment

October 8th, 2008 by k8gu No comments »

I contemplated using an original photograph to head this entry.  However, I couldn’t bring myself to do it.  Anyhow, words to shoot by:

In whatever picture-story we try approach the subject on tiptoe—even if the subject is still-life.  A velvet hand, a hawk’s eye—these we should all have.  It’s no good jostling or elbowing.  And no photographs taken with the aid of flash light, either, if only out of respect for the actual light—even when there isn’t any of it.  Unless a photographer observes such conditions as these, he may become an intolerably aggressive character. –Henri Cartier-Bresson.

» Read more: The Decisive Moment

Why does X cost so much?

October 3rd, 2008 by k8gu No comments »
Monetary instruments

Monetary instruments

For the third time in a month, I’ve seen a thread pop up on a ham radio mailing list or forum asking, “Why does X cost so much?” Morse code keys, amplifiers, and gin poles, were the subjects of “excess” expense. It doesn’t matter whether it’s a Begali or a Bugatti, a Henry or a Haliburton contract, a Rohn or a recession, some things are expensive, and many with good reason. Why is there a problem in the U.S. economy? We spent the money we once saved. Then we borrowed money we did not have from someone who was saving. Then we borrowed more money than we could ever pay back, sticking the lenders (arguably, the savers) with our debt and a fake smile. We bought things we could not afford. We did not (and do not) understand how much things cost. We became accustomed to spending too much for things we did not need. I suspect that the economic downturn is good for America in this regard…

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TS-930S power supply

September 28th, 2008 by k8gu No comments »
Benched TS-930S

Benched TS-930S

Remember how I said that I thought the W9RE switchbox had terrible isolation?  Well, although I didn’t measure it with a VNA, I was doing some testing the other day and noticed that it only seemed only bad when the left radio was transmitting.  For example, I put the left radio on 40 meters and the right radio on 20 meters.  There was terrible broadband hash whenever I closed the PTT line on the left radio.  So, I put the right radio on 40 and the left radio on 20 and transmitted again on 40.  No hash, just some faint trash that followed the keying.

I had noticed during the Sprint that the vacuum fluorescent display on the left radio was flickering following the keying.  But, I didn’t give it much thought until now.  I flicked the meter selection switch to Vc and sure enough, it was too high (>28 volts) on transmit.  Plus, it would spike and pin the meter whenever I released the key.

Today, I built a band decoder cable (fortunately, I had stocked-up on the mini-DIN plugs and the PIEXX board uses Yaesu BCD format) for the Yaesu FT-840 and put it into the left radio position. It’s clean, too.
The left ‘930 is now on my workbench, which is barely large enough for it.  It turns out that there is a substantial (4 volts peak-to-peak) ripple on the power supply when I close the PTT.  I sent a note to the TS-930S reflector; but, unless KA5IPF answers it, I’m probably on my own.  I suspect it’s just going to be a matter of disconnecting subsystems until I find the offender.

Until then, I’ll be using the FT-840 and the old TS-930 for SO2R.  But, at least I’ll be able to hear!  I’m also relieved that I probably won’t need to rewire W9RE’s switchbox.  I just need to build some short jumpers and W3NQN filters for all bands.

» Read more: TS-930S power supply

The problem with the gym

September 26th, 2008 by k8gu No comments »
Feet

Feet

Sarah has suggested several times that I should consider working-out.  A few weeks ago, she finally prevailed and I started going to the gym while she was doing water aerobics.  For me, going to the gym is a little like watching a childrens’ Christmas pageant.  You know it’s the right thing to do; but, it’s a little painful and worst of all, it’s mind-numbingly boring.  I had a good work-out today.  I actually was happy to be there for the first twenty minutes or so.  Have I pushed through the burn of boredom?  Time will tell.  I did feel like a million bucks when I finished.  I do enjoy that feeling.

» Read more: The problem with the gym

K8GU/9 – Urbana, IL

September 24th, 2008 by k8gu No comments »
K8GU/9 shack

K8GU/9 shack

80 meters and the Moon

80 meters and the Moon

This is my humble station in Urbana, IL. Inside, I have:

  • Kenwood TS-930S/AT with PIEXX digital upgrade (5-million S/N)
    • Inrad #103 and #104 400-Hz CW filters cascaded
    • Inrad #94 and #96 2.1-kHz SSB filters cascaded
    • Inrad roofing filter
  • Kenwood TS-930S/AT with PIEXX digital upgrade (2-million S/N)
    • Kenwood YG-455C-1 and YK-88C-1 500-Hz CW filters cascaded
  • Softrock v6.2 40-/80- and 160-meter SDR front ends
  • Yaesu FT-840 with Inrad 500-Hz CW filter (not shown)
  • Astron SS-30 and RS-7A (not shown)
  • W9RE-style 6×2 switch (not shown)
  • KK1L band decoder and relay driver box (not shown)
  • Heil HM-10 headphone mixer for SO2R
  • Homebrew W3NQN 200-watt transmitting bandpass filters for 160-20 meters
  • IBM Pentium 166 MHz 80 Mb RAM w/ Windows 95B
    • TR-Log
  • Dual Pentium III 500 MHz 512 Mb RAM w/ Windows XP and Xubuntu
    • N1MM
    • VE3NEA Rocky

Outside:

  • 10/15-meter fan dipole at 25 ft
  • 20-meter dipole at 35 ft
  • 40-meter dipole at 40 ft
  • 80-meter dipole at 40 ft (open-wire feed can be fed against radials on 160 via shack-operated relay)

The 10-40 dipoles favor the E/W direction, although on 40 most of it goes straight up. The 80-meter dipole would favor N/S if it mattered. If I install any new antennas this Fall or Winter, they will be receiving antennas for 40-160. We hope to leave Urbana in the Summer of 2009. Destination TBD.

Stored hardware:

  • Two KLM KT-34XA 32-foot boom tribanders
  • Hy-Gain 402BA-S 2-element 40-meter yagi
  • Mosley TA-33jr tribander (no boom)
  • Lots of wire and coax
  • 100+ ft of 7/8″ hardline
  • Hy-Gain T2X Tailtwister
  • 50 ft of Rohn 25G and accessories

» Read more: K8GU/9 – Urbana, IL

Linux on the small

September 20th, 2008 by k8gu No comments »
Linksys Router

Linksys Router

A few weeks ago, Sarah and I attended an event that the University YMCA sponsors…Dump and Run.  The idea is that students who are moving out in the Spring can drop anything they don’t want at the Y, which is within walking distance of the dorms.  Volunteers sort the items and sell them again in the Fall when the students return.  Many universities have variations on this theme.

I picked-up a nice framing square for 50 cents, a corduroy jacket for five dollars, and a few other odds and ends.  But, the big jackpot was a Linksys WRTSL54GS router.  There was no price on it and no price for routers or networking equipment on the general Dump and Run pricing sheet.  The top and bottom covers had been removed.  So, I had no idea if it had been “repaired.”  I offered the guy at the table five bucks for it.  He seemed happy; I was happy.

I plugged the little box in at home and fired-up my computer.  I was greeted by Whiterussian 0.9 instead of the usual Linksys firmware.  Brilliant!  Although I’m a fairly experienced Linux user, I’d never worked with embedded Linux.  So, I read up on it.  Not knowing if the previous owner was trying to launder a box that had been used for criminal intent, I reflashed it with a more recent edition of OpenWRT.  This gave me a fresh slate to work with to boot.

I shot Scott, KA9FOX, who hosts this site, a note about setting up a subdomain to use with router.  He suggested that the easiest way to do this would be to setup a free domain with dynDNS and then create a DNS CNAME record for home.k8gu.com that pointed at that domain.  Brilliant again!

One of the nice things about the WRTSL54GS is that has a USB port.  So, you can attach mass storage devices to it.  I’ve attached a 128-Mb jump drive that seems to work just fine.  But, I plan to do something semi-permanent at some point in the future.  There is a set of pads for a second USB port on the board, which are rumored to be hot.  I have contemplated hard-wiring an SD-card reader into that port to make a complete package.   Did I mention that I’m also using this as a wireless access point?  It’s great for the power misers out there.  It doesn’t quite have the umph to run SQL, as far as I know.  So, it wouldn’t be too useful for a self-hosted blog.  But, it seems very capable…  I’m already looking for another one; but, I doubt I’ll get that kind of deal anytime soon.

» Read more: Linux on the small