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Archive for 'Everything Else'

Pete’s house has a great view of the downtown area of Indianapolis. Humidity was high, but we I managed to get a couple of decent shots of the festivities…

THAT…

WAS…

GREAT…!

…I even went back to verify the whole “jacket / no jacket” thing in Episode 5 [17.55] and it really does check out….

…and YES that was the Egyptian sarcophagus from “Pyramids of Mars”

BRILLIANT!

My only slight niggle was that Philip Madoc wasn’t in it – and neither was the “Time Lady” as reported by IMDB, but then removed

:(

Welding! again…

OK so after some intense welderization I can just about do this:

I call it “Arbitrary Metal Thing #1″

After I was done I threw it up the street a couple of times to “test the seams” and it held together quite well.

And I got a nice welder’s sunburn on my left forearm on the bit that was exposed to the arc.

Which was nice.

And I thought I had the only Police Box in Indianapolis – looks like someone has built one on the west side of town.

So much for the perception filter.

Welding! Or kind of…

I’ve been putting this off for *ever* but today I went out and bought myself a welding kit from Lowe’s.

I bought the Lincoln Electric 140 amp model, as it was the highest output that could still run on 120V. It supports gas shield, and flux core welding and comes in a natty red colo[u]r.

Basically you pass about 90A at 19V through a very thin piece of wire, the wire melts and fuses with the two pieces of metal you are trying to join.

Even though it’s hotter than heck outside I managed to keep all the safety gear on just for long enough to do this…

And here it is with the “slag” removed…

This is, of course, complete rubbish – but not too terrible for my very first try. The two pieces of steel are well and truly stuck together.

It’s going to take a lot of practice before I can make one of these:

Cue the music…

I recently received the link to Wicked Lasers by a workmate looking for my feedback on the latest product offering – a handheld blue laser with an output power of 1Watt (yes, 1 Watt) for $197.

The apparent similarity in design to a lightsaber handle is completely accidental.

Link Here

At first I thought it was the usual malarky – diode from Blu-Ray, misrepresenting the power, wrong price… But no, it actually seems to be genuine.

Up until recently true blue lasers have been very expensive (several thousands of dollars for relatively low power devices), but the new 445nm modules are the first of a new wave of direct laser diodes – devices that produce the output color directly, rather than produce an intermediate color first, and then convert.

I’m actually kind of amazed that these thing are for sale at all. A 1W laser is *insanely* dangerous. Even viewing the reflected dot from a white surface is enough to do permanent eye damage. Up until now my high power experience has been with 600mw green lasers – and these were scary enough.

So anyway, after much deliberation, I decided to place an order for one.

Just to see what all the fuss is about.

The last time I checked Wicked Lasers was about a week out on filling orders, but with all the attention the site has been getting recently I don’t expect it to show up any time soon. Before I bought it they made me complete a waiver that ensures I’ll use it responsibly.

But to quote someone on a recent forum: “If I can’t point it at objects, or people, or the sky, or a wall – then what the hell can I do with it??”

This video was embedded using the YouTuber plugin by Roy Tanck. Adobe Flash Player is required to view the video.

This is an implementation of the recent article on instructables.com describing a Twitter World Mood Light, ported to use the WiShield wireless networking device.

I thought that the idea of creating an embedded device that can perform complex analysis of realtime data, and then go on to produce a simplified result to be fascinating. So I had to build one. I just couldn’t bring myself to pay $90 for the WiFly, and found the WiShield at a more palatable $55. The biggest issue with processing web data in a microcontroller is that you just don’t have enough RAM to capture the whole page, so you have to process it in smaller chunks.

The original article is here:
http://www.instructables.com/id/Twitter-Mood-Light-The-Worlds-Mood-in-a-Box/

Even though the Twitter interface is working very well, I currently have my doubts about the LED – it’s not changing to the correct colors at the moment, need to check my wiring, and then take a look at the update routines.

    bool GetHttpWebRequest(char* s)
    {
      // Create the webrequest
      GETrequest getTweets(twitter_ip, 80, "www.twitter.com", s);
      getTweets.setReturnFunc(printData);

      getTweets.submit();

      int count = 0;

      // Process
      while(getTweets.isActive())
      {
        WiServer.server_task();
        delay(10);
        count++;

        // Timeout = 20 seconds approx
        if (count > 2000)
           return false;
      }

      return true;
    }

UPDATE: I found out what was wrong with the LED – the library (as supplied) subtracted color values from 255 when setting the pins, I don’t think this is correct – it should set the color values directly – like this


    // replace this
    analogWrite(m_redPin, 255 - currentColor.r);
    analogWrite(m_greenPin, 255 - currentColor.g);
    analogWrite(m_bluePin, 255 - currentColor.b);   

    // with this
    analogWrite(m_redPin, currentColor.r);
    analogWrite(m_greenPin, currentColor.g);
    analogWrite(m_bluePin, currentColor.b);   

wherever analogWrite is called in LED.cpp.

UPDATE UPDATE: I had a quick chat with the original developer and his LED could well be an inverse configuration to mine – so this fix might not be necessary, depending on the type of LED you use.

Philip Madoc in "The War Games", along with Harold Meeker...

As an old-school Doctor Who fan, I know that Philip Madoc has been in more episodes than I can remember (and as Han Solo once said ” I don’t know, I can remember quite a lot…” – or something like that).

I’ve recently been watching “A Mind To Kill” – starring Mr Madoc as a kind of Welsh Inspector Morse – and the thought occurred to me “How come Philip Madoc hasn’t been offered a role in the new Doctor Who?”

Then I saw this:

http://www.imdb.com/name/nm0535053/

Yay! How cool is that? – Steve Moffat is literally reading my mind…

This video was embedded using the YouTuber plugin by Roy Tanck. Adobe Flash Player is required to view the video.

This has to be one of the best pieces of software I’ve seen. It’s a realtime physics modelling engine for kids called Algodoo.

http://www.algodoo.com/wiki/Home

You can create simple machines out of basic shapes and other entities then enable gravity and air resistance and see what happens.

One of my favo[u]rite things to do is liquefy solid objects and watch things come tumbling down.

But then I’m like that…

This video was embedded using the YouTuber plugin by Roy Tanck. Adobe Flash Player is required to view the video.

First experiments with an electromagnetic pendulum.

The pickup coil (a steel bolt with about 100 turns of enameled wire) picks up the passing of the magnetic pendulum. This is then fed into a microprocessor that energizes the coil just long enough to give the pendulum a push.

This is the basis for the next clock I build on the new CNC.

(The Arduino is included purely for blog cred…)

Now I just need to design a suitable escapement…