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Journal Journal: T-Rex 500 maiden flight 1

I got my new T-Rex 500 in the air for the first time on Christmas Eve, and again on Boxing Day. It has three flights on it now, and no, I didn't crash it :-)

I didn't do anything particularly exciting on these first flights, because I'm still tweaking the setup. On Boxing Day, I didn't even do any tweaking, there was an icy 15 mph easterly wind that made me give up before I even finished the battery packs - I could no longer feel the transmitter sticks my fingers had got so cold. (However, it flew really well in the wind, it would have been like trying to fly in a washing machine with my HDX-300 heli).

It's absolutely fantastic. And it was worth all the time spent on getting the rotor head setup just right - the first liftoff, it lifted off into a perfect hover with absolutely no surprises. It's just the tail I need to tweak (and that really must be done by flying and tweaking, rather than on the bench). My local RC shop lent me a very good pitch gauge, so I could set up the blade pitches and this meant the tracking was perfect on the first liftoff.

Here's a pic of it sitting on the table. I will take some in-flight photos tomorrow if the weather allows.

http://www.alioth.net/tmp/trex1.jpg The whole heli
http://www.alioth.net/tmp/trex2.jpg Tail detail, also showing the bevel gears from the driveshaft (or torque tube, as Align calls it)
http://www.alioth.net/tmp/trex3.jpg Rotor head detail

User Journal

Journal Journal: Introducing Friends and Family to Mexican Cooking 3

There's not a lot of it about here, so...for an early Christmas dinner...

Last night, I made tacos (actually started the night before, the filling is best, I find, made the night before and allowed to marinade in its own juices for a night). I used Alton Brown's "Good Eats" recipe for the guacamole, it's a good recipe. Also made salsa too. I found some "Quark" brand cream cheese so I had to use that, too!

And margaritas. It's not a proper Mexican dinner without a certain tequila element. It went down very well, between 4 of us we finished off all the margarita mix in less than an hour...and there was half a bottle of tequila in it. Not to mention the triple sec. I think all the food must have ballasted the booze a bit because I didn't feel at all wasted.

I still have some taco meat left, so guess what I had for tonight's dinner :-)

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Journal Journal: T-Rex 500

Sod the credit crunch. I just got myself a new RC helicopter, a T-Rex 500 ESP. It comes as a kit, and I got it on Saturday and had it almost complete by Sunday evening. However, I needn't have rushed, because the weather looks terrible for the next few days.

Compared to my current HDX-300 heli, it looks huge. The rotor disc is just under 1 metre, and it's powered by a big chunky brushless motor and vast Li-Poly battery (actually, two of them in series). It's no wonder Align (the maker of the T-Rex series) has such a good reputation - the engineering is beautiful, everything fits together perfectly, with no slop in the rotor head whatsoever. This kit has a shaft driven tail (most helis use a belt) which hopefully will be more efficient, I think the belt tends to rob quite a bit of power. My only grumble about the kit is it uses lots of 2.5mm socket screws and 2.6mm socket screws, rather than just sticking to one size. The trouble is a 2.5mm allen key fits the 2.6mm socket and tightens it most the way, until it starts to torque up then the allen key slips and strips out the head of the screw such that the proper 2.6mm allen key won't shift it - and a 2.5mm allen key looks just like a 2.6mm one so you don't know you've done it till it strips it.

But other than that it's pretty much perfect. I put the supplied main rotor blades on my blade balancer, and they balanced perfectly out of the box. I've never had that happen before. I can't wait to fly it, but at the same time I'm terrified of crashing something so beautiful! (I think I'll do the test flights in a wiiiiiide open space, I won't make the mistake I did with the HDX-300, doing the maiden flight in a constrained space!) The other thing about this heli, although people say it's a park flyer, it certainly looks big enough and feels heavy enough that it could cause much pain and suffering, so it ought to be preflighted just like a full-scale heli before flight.

Interestingly, I asked the guy who owns the model shop how he's doing in these credit-crunched times, and he says he's already sold more this December than he did the whole of last December, so it seems like at least the model-buying public are saying sod-the-credit-crunch.

User Journal

Journal Journal: Too big to fail? 5

Perhaps, in the Brave New World following all the financial crashes, there ought to be measures (perhaps added to anti-trust legislation) preventing any company from getting Too Big To Be Allowed To Fail. Perhaps the Big Three automakers should be broken up so they are the Much Smaller Nine?

Discuss.

User Journal

Journal Journal: Google Languages

I've found a useful trick while trying to write things in Spanish - if I'm not sure what I'm writing is correct, is to put the phrase I'm writing in quotes in Google. If it's right, I'll get lots of hits with the sentence fragment in context, where I can sanity check (and often learn something new). If it's wrong, I get few results. I have set my computer's language to Spanish so I get the Spanish Google by default.

User Journal

Journal Journal: A sad, sentimental journey

A bit of a break from the usual geekiness on this channel, it's time for some human nature stuff.

On Wednesday, I went over to England with my Dad in The Truck of Love (a 7.5 tonne M.A.N lorry, the story of why it's called the Truck of Love can wait). The purpose was to go to Worcestershire and clear out my grandparent's house, which has just sold.

These were my grandparents on my Dad's side (my Grandfather on my mother's side is still going strong, and we had Sunday lunch with him). We stayed with my aunt and uncle in Worcester, which was quite interesting as my aunt is as mad as a box of frogs (in a good way. In fact, that entire side of my family is eccentric, that's where I get it from. For example, my Uncle Bob *still* hasn't left home and he's well into his 50s. And he only has a motorcycle license, and about 10 motorcycles, of which only one is functional at any one time. Others on that side of the family are still living in the temporary buildings, as they put a new roof on the house. They started that job in the 1970s. Oh well, there's time enough!)

On Thursday to Saturday we cleared out the house. We got it mostly done by the end of Friday, and on Saturday just needed to vacuum the floors and close up each of the rooms.

It was then the sadness started. Looking out of the lounge windows for the last time, into the garden illuminated by the feeble winter sunshine, glistening off the damp trees and grass.

My grandparents had that house built for them in the mid 1960s. It's a modest bungalow in what was then a new suburb in a village near Worcester. My Dad lived there too in his late teens. I remember going there with a lot of excitement as a small child, playing in the garden that seemed like acres when I was small. And still seemed like acres when I had to mow it when I was in my teens, after my grandfather had a stroke and wasn't fit enough to do it himself any more. There were so many memories of hot summers, endless pots of tea, my grandmother trying to be like Hyacinth Bucket, my grandfather telling her not to be so silly... little things like finding the snow shovel my grandfather made (he went through several iterations of trying to design the ultimate snow shovel, the latest of which, with "Experimental Daisy" written on it in marker pen in his writing is still in the garage for the new owners of the house. I don't know why he called the snow shovel "Experimental Daisy"). It just brought back a lot of sadness that now the door is closed on that forever.

I think both my dad and I were twinged with guilt when we got rid of the terrible particle board furniture my grandmother thought was the bees knees (very 1960s "Space Age" stuff, and absolutely hideous) and all of that yellow and orange patterned stuff that was so popular in the 60s and 70s that my grandparents never got rid of. I can remember them having it when I was a few years old. We had to be brutal in what we got rid of, there was only limited space in the truck, and there was furniture that had to be kept.

In this contrast of 60s dross ("everything must be new", my grandmother had specified), was some of the furniture they had kept from their previous house. I now have the oak dining room set that they had made for them in the 1950s. It must have cost them a significant fraction of their annual income - given that my grandfather ran a baker's shop in Worcester (the type that has nearly died out now, where the owner bakes all the bread and sells it in the same shop, and it's a standalone family business run in a building about the size of a normal house). The dining room table and cabinet was made bespoke and is all hand carved. To get something made like that now would cost several thousand, in fact probably still a large fraction of a typical middle class annual income - it must have taken years of savings in the 1950s for someone running a small family business. I think they would like it that it is still staying in the family.

I also kept the radiogram (a record player and radio combined) that they must have bought new in the mid 1960s. I thought it had valves (vacuum tubes) but it's all solid state. The record player still works but I couldn't get anything more than hiss out of the radio. Unfortunately, the instruction manual (which it still has!) does not have a schematic, which is quite unusual as many appliances of that period came with schematics so that you could repair them. There's also quite a bit of hum, so I suspect the filter capacitors on the power supply aren't in all that good shape. I'd like the radio to work (to give you an idea of its era, the manual talks of an add on you will be able to buy if stereo radio broadcasting becomes a reality!) - hopefully it's not some unobtainable germanium transistor that's gone phut. It'll be good to get it to work as the radio for my retrocomputing room (although I'll need a short range FM transmitter so I can listen to BBC 6 Music)

The house is sold now, and it's the end of an era. I have the last apple I will ever eat from that garden in the kitchen. Perhaps I ought to see if I can get some of the seeds to germinate. I hope the new owners like the house and enjoy the big garden that my grandfather specified on the original plans.

User Journal

Journal Journal: More motorcycle WTFs 6

It turns out the real WTF on the turn signal circuit was not that the flasher unit was 2 pin (when I studied the bike's schematic, it quickly became obvious that a 2 pin flasher should work just fine), but that it was plugged in wrong. So when I rearranged the connector, it all worked.

I discovered another WTF while debugging the brake light circuit this morning. Neither front or rear brake switches will light the brake light. I took the front light switch off and found it worked, but the circuit from the front had gone high resistance (a contact needs cleaning somewhere). I then tried to take the rear light switch off... and discovered that it is the *only* Imperial fitting on the whole bike. Everything else is metric, apart from the rear light switch. WTF? Of course, I only have metric tools, and my adjustable wrench is a huge thing that can't grip the hex nut on the brake switch, which falls neatly between a 10mm and 11mm spanner (I suspect it's a 1/2 inch nut). I can't imagine the Italians fitted an imperial part to the bike when it was new (the hex nut is part of the switch assembly, not a separate nut - it's sort of cast into the switch's housing) so I'm betting it's a replacement.

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Journal Journal: Roundup-Ready JE: Moto-WTF, a bit of buzz, más espa&#2

So last weekend, I thought I'd find out why the indicators are only working on one side of the motorcycle. The reason became very clear when I looked at the flasher, in preparation to tracing the power to each blinker...

The Mito's flasher circuit requires a 3 pin flasher, with an input pin, and one pin for each side of the bike.

The flasher on the bike... had two pins, and the circuit for the entire right side was just left dangling.

I have to wonder WTF the last owner was thinking when he fitted that! Unfortunately Road & Track didn't have a 3 pin flasher when I dropped in there today, so I'll study the wiring diagram and see if I can make the 2 pin flasher work (I suspect it's not all that hard). Otherwise I'll have to either build a solid-state flasher or get one on the internet.

It turns out that the video I made last week of my Sinclair Spectrum doing streaming video with the ethernet card I made has caused a bit of a buzz. The video has got around 1100 views in just 5 days, not bad for a demo on some ancient hardware! I also got contacted by the editor of RetroGaming who wants to put something in the magazine about it. (I've also ordered some more W5100 chips, I think there's enough interest that some Speccy enthusiasts would like a Spectrum ethernet card of their own).

Finally, más español. I've got to the point that I can hear nearly every word spoken on telemadrid's news, and on the BBC Mundo podcast, even if I don't understand a lot of the words. Spanish no longer sounds like random jabbering but actual words. There are some words I have trouble with distinguishing still (and usually realise a few words later in the sentence that the word I didn't get was perhaps two words, or perhaps just one word which I thought was two, or was in the pretérito perfecto, (past perfect tense, which in English is made up of 'to have' plus verb, for instance "he has made", the structure in Spanish is very similar, haber + participle, for example, ha hecho). But when spoken quickly, because the H isn't pronounced in Spanish, I can sometimes miss it and therefore lose the meaning. Another good bit of progress is when reading Spanish, I can quite often understand words I don't know by working them out from context, or by using the Spanish dictionary and *not* the Spanish to English dictionary. (I usually look up words I guessed from context, or guessed because they are similar to English words - there are a lot of "false friends" between Spanish and English).

User Journal

Journal Journal: Good grief, what have they done to Slashdot? 2

First the firehose was made useless, and now the front page. I had to click on three different journal links to find the "Write in journal" link to actually write this little rant.

Please, CmdrTaco, do an "svn revert" to the revision before the Firehose was changed. The new front page in particular is awful, because now you have to click on each link and wait for the page to load to see the story summary (no keyboard shortcut even!) instead of simply scrolling down the page. One thing that set Slashdot apart is that the front page was easy to scan for interesting stories because a decent summary was shown.

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Journal Journal: Streaming video on a Sinclair ZX Spectrum...

My current electronics project (well, now it's really become a software project, the software has taken about 10 times longer to make than the hardware) is a device called the Spectranet, an ethernet card for the Sinclair ZX Spectrum.

Yesterday, I made a Spectrum do streaming video over the network!

Here's a short video of, well, the video.

http://www.youtube.com/watch?v=hf8rz0sb298

I was suprised that my socket library was fast enough (there's some overhead in managing the ethernet buffer, the W5100 ethernet IC puts data into a ring buffer, and all the values are all big endian and have to be turned into little endian, and there's a whole bunch of 16 bit compare operations that have to be done, polling for data, and all the rest). But when the video played pretty much at the correct speed...damn, that was cool!

No, before you ask, the Speccy doesn't do the soundtrack. Just the video.

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Journal Journal: Perhaps one day I can be bi 3

...lingual. I know I'm making progress with Spanish, because I chuckled at something in Spanish for the very first time yesterday!

It was a particularly weak joke, but I got it! It was, however, written rather than spoken. I still have a really hard time understanding spoken Spanish... but I've only been since May - so I think to actually get a joke is a bit of a milestone. For your gratification, if you understand any Spanish, here it is:

Se abre el telón y aparece un miembro del foro intentando mear pero por mas que se esfuerza no lo consigue. Se cierra el telón. Como se llama la peli ?

"Micción" imposible.

(damn, Slashdot won't do an upside down question mark)

It was even a play on words, but it's actually a joke that works in English too so it's only a beginning. But it is a milestone to actually chuckle at something I just read in Spanish. It means I've made more progress!

My goal, incidentally, is to have reasonable competence with the language with 2 years study. If I've not said it yet, I'll say it again...learning a human language is 100 times harder than any computer language.

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Journal Journal: HeliFrustration

So, finally, I got around to rebuilding my HDX-300 RC heli after The Big Crash. The Big Crash was not caused by my own incompetence (for a change) but rather the ESC deciding to go intermittent in flight, causing a power loss. The HDX-300, being quite small, doesn't autorotate very well, but it does. That wasn't really the problem though. The power came back just before the heli touched (well, thumped) down, and the heli took off in an unexpected direction.

Before I could stop it, it had hit the rocks at the edge of the pond and then bounced into the pond. It would have sank all the way to the bottom if the main rotor hadn't been supported by some pond lillies. The main rotor was wrecked by contact with the rocks (the blade tips splintered), and the shock had bent the hardened steel main shaft and cracked half of the carbon fibre frame. Fortunately, the crash impact had flicked the battery out, which I found lying beside, but not in, the pond! So the electronics survived.

Since I've been busy with too many other projects, I've only just got around to rebuilding it. While running it up to check the main rotor blades were tracking correctly, one of the tail rotor blades flew off - the bolt securing it down didn't have any thread lock on it (I'd never actually removed it at all, it had done plenty of flying without incident). But the imbalance this caused bent the tail shaft. So I got a replacement, which I fitted tonight, along with a larger pulley at the other end of the belt, to increase tail rotor speed (the only thing that's bugged me about the HDX-300 is the tail rotor isn't powerful enough, so the bigger pulley puts a few more RPMs on the tail rotor). The new shaft, though, must have had a metallurgical flaw. I was doing the first test flight, and the heli was just out of ground effect when I heard a "thwack" and the entire tail rotor flew off. The heli of course immediately started to spin, but I could just dump the collective at this stage.

So it's been very frustrating. I've ordered some new tail shafts, hopefully they won't have the same flaw!

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Journal Journal: It starts! 1

I'm finally in the putting-back-together stage of overhauling the motorcycle I bought in August. I started it for the first time this afternoon... and it actually started up! It even idled OK with the choke off after a couple of minutes running. Typical obnoxious 2-stroke sound though :-)

Here's a picture from August when I got it:
http://www.alioth.net/tmp/cagiva.jpg

Currently, the fairings are all off it, so unlike the photo, it looks kind of "naked". The work I've done so far:

New front brake disc and brake pads.
New rear brake pads, rear disc reconditioned.
Minor cosmetic repair work done to the exhaust (clean up all the rust and loose paint, replace the broken spring, and repaint).
New front forks.
New rear shock absorber.
New rear wheel bearings
New sprokets and chain.
Clean up and repaint headlight/instrument frame.
Clean out fuel tank, fuel filter etc.

Still needing to be done:
Find new instrument mounting rubber mounts. (These seem surprisingly hard to get).
Check that the front fork settings are actually correct.
Replace brake light switch.
Replace right rear turn signal lens.

Oh, and I have to do my CBT so I can actually ride the thing, get it taxed, insured etc.

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Journal Journal: The future of lighting...almost here?

I've now made 3 Luxeon Rebel based lighting modules to play around with (each with a PCB with the current regulating supply and two LEDs, ridiculously over-heatsinked with old heatsinks off Pentium 66 processors - well, they were free!). Here's a pic of the modules I made:

The naked LEDs on the PCB:
http://www.alioth.net/tmp/rebel-naked.jpg

And with the lenses:
http://www.alioth.net/tmp/rebel.jpg

In use, the PCB won't be seen, it'll be the other side of the roof of the boat it's going in (there will be holes drilled in the ceiling where the lenses poke through, kind of like how halogen downlighters are usually fitted in a ceiling).

I've been using the three modules to light my computer room for the last couple of days, they've just been sitting on my table shining upwards at the ceiling.

Each module uses about 3 watts, and the three of them together provide a similar amount of light as the 9 watt compact florescent that I normally use.

I do like the quality of the light. The LEDs I'm using are the most efficient type of Rebel (since in the intended application, efficiency is king). Even last year, the white Luxeons you could get weren't actually white - they were pale violet (my bike headlight is this kind of LED). Also, for a couple of years it's been possible to buy GU10 style downlighter LED modules. These again are pale violet rather than true white. They claim to be equivalent to 25W halogen, but having tried them, I'd say they are at most equivalent to 5 watt halogen - the claims on the box are grossly overstated (the GU10 LED units are very narrow beam. Perhaps it's the equivalent of a 25W halogen if you're right in the beam, but that's it).

But the latest Luxeon Rebel LEDs are actually getting there. They are bright enough and the quality of the light is good enough that I could make some home light fittings that use them with the wide angle diffuser/lenses that I'm using for the boat. What holds them back from general usage, though, is the expense of acquisition. Each of those tiny LEDs in small quantities costs the equivalent of about US$7, and you need 9 of them to get about the same level of lighting as a 9W compact florescent. They do, however, last 50,000 hours - if you were using them for 6 hours a day, they would last 22 years!

In conclusion, LEDs have got good enough now for specialist lighting - the whiteness is now good, and the efficiency is good (for instance, the roof space of my Dad's boat is far too constrained for a compact florescent downlighter, and halogens run too hot and are not efficient enough - so these LEDs fill that niche well). However, they still are too expensive for general home lighting. But in five years? The story may well be different.

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