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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 :-)

Comment Re:Not just cost, but optics (Score 1) 685

I've made LED lighting units for my Dad's boat, so I'm passingly familiar with the subject.

No, it's nowhere near as difficult as you state. The Luxeon Rebel with the Lambertian pattern with no lens put over the LED has an illumination angle approaching 180 degrees. That is NOT narrow angle. To make an omnidirectional lamp you'd only need to put two of them back to back, or if you're fussy you can put three in a triangular arrangement. I'm using these LEDs as downlighters though, so I did use a lens to make them *more directional* because the beam was far too wide. They are plastic, and inexpensive, and contain a reflector. The lenses I used give the lighting pattern of a typical halogen downlighter.

The problem with LEDs isn't the illumination angle, simply, at the moment, it's cost. The best Luxeon Rebels are now about the same efficiency as a compact flourescent, but a 3W LED costs about two or three times the price of a 9W compact florescent - and that's without the lens or power supply. People normally can't see past the acquisition cost either, at the 50,000 hour lifespan (guaranteed to produce 80% of rated lumens at 50,000 hours at rated current). If you used the light for 8 hours a day, every day, that's 17 years - and they don't have the warm-up issues of a CF lamp.

The future is LEDs, just give it three or four years, and the costs will come down to a level that won't make most people wince.

Comment Re:batteries? (Score 1) 275

You misunderstand quite completely. A capacitor (or any power source for that matter) will only release energy as fast as its demanded. If you had the ideal 12V voltage source (i.e. a 12V voltage source that could give infinite current given the ideal short circuit), and put a 12 watt bulb across it, only 1 amp will flow at 12 volts.

Read about Ohm's Law here to get a deeper understanding: http://www.ibiblio.org/kuphaldt/electricCircuits/ (and if you want further understanding still, read about the Thevenin Equivalent Circuit).

Comment Re:No players on the market (Score 1) 308

Building a SCSI interface is something easily within the reach of the electronics hobbyist, as is an IDE interface (in fact, an IDE interface is trivially easy to make for anyone with some practical digital electronics experience). There are USB FIFO chips on the market that should make it relatively straightforward to make a USB - SCSI adapter for old drives. While 8 inch disc drives are as common as rocking horse shit, 5.25 and 3.5 inch disc drives were made in huge numbers so there's no real shortage of those. (My 25 year old 5.25 inch discs all read perfectly), and 5.25 inch drives aren't difficult to repair. Floppy disc controllers are still pretty easy to get hold of - any self respecting electronics junk shop should have some WD177x types in stock still, and they come up on ebay quite frequently. Even when they get hard to find, it would be perfectly possible to roll-your-own disc controller with a CPLD and a handful of discrete components.

Comment Re:What does HP use??? (Score 1) 223

These machines were in 35 different locations, not all in the same place...and other machines didn't have a problem. It was only the HP desktop machines. This is actually the second "bad caps" issue we've had with these machines, all the motherboards were replaced under warranty, as they started failing (with bulging caps) within 6 months of being installed. The power supplies started failing 2.5 to 3 years after the machines were put into service.

The capacitors were (according to the rating printed on the can) adequately sized, they were just crap.

Comment Re:Nothing new (Score 1) 465

Don't forget embedded. Everyone forgets embedded, despite you having probably more embedded devices in their house than desktop computers!

Lots of assembly language used there. When you're trying to fit your washing machine code in an Atmel AVR with 1K of flash and 64 bytes of RAM, optimisation is important and throwing more hardware at it is expensive - because each instance of the software comes with an instance of the hardware, too. Anyone who likes getting down and dirty with the bare iron, try doing embedded. Or if it's just some fun programming you want to do, get a retrocomputer like a Sinclair Spectrum or Commodore 64.

Comment Re:This has been true since at least 1980. (Score 1) 465

The story is cute, but it also must be remembered that all the redundant code may also have unknown bugs and security holes. What would the cost of being pwned be? Would being pwned cost the company more than having good quality code without redundant and possibly exploitable internet-facing code that probably never gets tested?

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!

Comment Re:ScuttleMonkey doesn't even read TFS (Score 1) 300

It's worse than that, in around 1999 or so, I got a $10 charge on my landline bill (then GTE, now Verizon) for a "third party call" from Florida to New York when I wasn't even in the country. Apparently you can call the operator and have your call put on someone else's bill unless they have 3rd party call blocking...which costs money.

I was really tempted to cancel tone dialing service (GTE charged a few cents a month to let you tone dial!!!!) just to spite them.

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