I went to the Citroen garage to pick up my roof rack the other day, and do you know what? They had *five* different models of van. Five! Talk about fragmenting the market! Obviously everyone should all just use a Relay dually, because fragmentation is bad.
It gets worse though, because on the way out of there shocked by the fragmentation of five different models, I drove past the Peugeot garage - and *they* had five different models too! Then I drove past the Ford Commercials garage and my Transit-identifying neurons melted.
It can't be the money, either. Even the loaders (the guys who stick the wheelie bins on the lift and press the button, so not even *that* physically demanding) start on about £18k a year.
I've read where various chemistry experts essentially say that terrorists cannot construct liquid bombs that will work at all without having to basically use chemistry equipment, ice baths, lengthy mixing sessions that no one could possibly ignore, etc. Yet here the former TSA head insists that there is a very real risk here. Who is right? Does the former TSA head know something that chemistry experts have somehow missed?
The TSA are gambling on no-one within the US having done enough high-school chemistry to make it through an episode of Breaking Bad.
Any 13-year-old high school chemistry pupil ought to be able to tell you exactly why mixing nail polish remover and hair bleach isn't the same as mixing pure acetone and (reasonably) pure hydrogen peroxide.
If you have vacuum-assisted brakes, there's typically quite a large reservoir. Try it yourself; switch off your car's engine (while you're stopped, obviously) and pump the brakes a few times. You should get about 5-10 presses before the pedal starts to stiffen up.
Many modern cars now don't bother with a vacuum servo and just use pressure from the ABS pump, which is electric. A lot of old Citroens and Maseratis (and the Mercedes and Rolls-Royce cars that used a cost-reduced version of their hydraulic systems) use an engine-driven pump with a hydraulic accumulator to power the braking system - I've driven a Citroen XM about 30 miles with a broken hydraulic pump belt before the pressure warning light came on, with no reduction in brake capacity.
$1200 in NYC will get you halfway to owning a one room the size of a closet.
... and up here just about ten miles outside of Scotland's largest and most important city, Glasgow (sorry Edinburgh, I know you've got the Scottish Parliament building and all), the equivalent of roughly $700US gets you a two-bedroom farm cottage with a half acre garden. As an added bonus, London is hundreds of miles away.
I hit post instead of preview, damn. The other point is that I live in the UK and I am currently breaking the law by *not* owning a gun. A few minute's work with Google should explain all...
Hey, I'm just going by what I read off the airport weather station. Cyclone Ulli mostly hit the south of England, where it caused a lot of damage because they rarely get much wind. That's in a different country a very long way from here, though, and all we really got was a few slates off and a couple of trees down.
Well, you know your 140mph hurricane-force winds? We call that January. This year has been unusually calm in that we didn't seen much over 100mph, but you get some years like that and you get some years where it doesn't go below 90mph for a week.
... try not building your house in an area prone to hurricanes. Or, if you're going to do that, try not living in a house constructed along the same basic design as a plywood packing crate.
Most of the houses in the US would simply not be passed as fit for human habitation in the UK, because of their shoddy thin-crappy-wood-over-thin-crappy-frame construction.
If you have to rip apart walls - or even just skim them before you paint or paper - take the time to run in plenty of cabling. You can get audio and video baluns for running over CAT5 these days fairly cheaply, although the hifi purists will throw their hands up in horror.
CAT6 is cheap enough, might as well start ahead of the curve.
So, it's a Bad Thing that they speak Punjabi as a first language? And yes, if it was Welsh or Gaelic then it would be a great example of progressive education saving their heritage...
I think you're rather missing the point. The fact that SDR *is* software-defined is what allows you to use an FIR filter.
What sort of hardware you implement this on is irrelevant. Even supposing you use a pair of ADCs hooked to an FPGA and implement the whole thing in the FPGA, it's still software.
In a conventional radio receiver, you start by filtering off the wanted signal with a broad filter, mixing it with another locally-generated signal (the Local Oscillator) to make a lower Intermediate Frequency (IF), then filtering the IF to extract a single "channel" of information. Then you demodulate this, possibly after mixing it down to an even lower IF.
In a software-defined radio, you convert directly down to a much lower frequency (audio frequency, even), but - and this is the clever bit - you do it with two local oscillators, 90 degrees out of phase. This gives you a complex sample, a pair of samples representing In-phase and Quadrature, or the real and imaginary components of your signal.
From there you can apply digital signal processing techniques to extract the wanted signal, show an FFT of the chunk of band you're capturing, and so on. This lets you do very sharp filtering, because you're no longer constrained by the physical realities of trying to implement electronic filters with practical components.
Shameless plug - if you want to try SDR out, go here: https://github.com/gordonjcp/lysdr Follow the instructions in the README, then either post a reply or bug me in irc.freenode.net ##electronics for further instructions.
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You didn't mention software-defined radio, where some of the most exciting developments are happening ;-)
I went to the Citroen garage to pick up my roof rack the other day, and do you know what? They had *five* different models of van. Five! Talk about fragmenting the market! Obviously everyone should all just use a Relay dually, because fragmentation is bad.
It gets worse though, because on the way out of there shocked by the fragmentation of five different models, I drove past the Peugeot garage - and *they* had five different models too! Then I drove past the Ford Commercials garage and my Transit-identifying neurons melted.
Fragmentation! Aaaaaargh!
It can't be the money, either. Even the loaders (the guys who stick the wheelie bins on the lift and press the button, so not even *that* physically demanding) start on about £18k a year.
Why isn't there a big media-driven push to get more women driving trucks for the cleansing department? Isn't this sexism too?
I've read where various chemistry experts essentially say that terrorists cannot construct liquid bombs that will work at all without having to basically use chemistry equipment, ice baths, lengthy mixing sessions that no one could possibly ignore, etc. Yet here the former TSA head insists that there is a very real risk here. Who is right? Does the former TSA head know something that chemistry experts have somehow missed?
The TSA are gambling on no-one within the US having done enough high-school chemistry to make it through an episode of Breaking Bad.
Any 13-year-old high school chemistry pupil ought to be able to tell you exactly why mixing nail polish remover and hair bleach isn't the same as mixing pure acetone and (reasonably) pure hydrogen peroxide.
âoeThey did the worst thing they could do to someone who is used to working 80 hours a week,â Mr. Palmer said.
Why the hell would you work an 80-hour week?
If you have vacuum-assisted brakes, there's typically quite a large reservoir. Try it yourself; switch off your car's engine (while you're stopped, obviously) and pump the brakes a few times. You should get about 5-10 presses before the pedal starts to stiffen up.
Many modern cars now don't bother with a vacuum servo and just use pressure from the ABS pump, which is electric. A lot of old Citroens and Maseratis (and the Mercedes and Rolls-Royce cars that used a cost-reduced version of their hydraulic systems) use an engine-driven pump with a hydraulic accumulator to power the braking system - I've driven a Citroen XM about 30 miles with a broken hydraulic pump belt before the pressure warning light came on, with no reduction in brake capacity.
$1200 in NYC will get you halfway to owning a one room the size of a closet.
... and up here just about ten miles outside of Scotland's largest and most important city, Glasgow (sorry Edinburgh, I know you've got the Scottish Parliament building and all), the equivalent of roughly $700US gets you a two-bedroom farm cottage with a half acre garden. As an added bonus, London is hundreds of miles away.
Why would you get stopped for having a broken door lock?
It's not a law from hundreds of years ago, it's current (but not particularly enforced). Oh, you can't see this. Never mind.
I hit post instead of preview, damn. The other point is that I live in the UK and I am currently breaking the law by *not* owning a gun. A few minute's work with Google should explain all...
Burglary rates aren't especially high in the UK. The murder rate in the US is insanely high, though.
Hey, I'm just going by what I read off the airport weather station. Cyclone Ulli mostly hit the south of England, where it caused a lot of damage because they rarely get much wind. That's in a different country a very long way from here, though, and all we really got was a few slates off and a couple of trees down.
Well, you know your 140mph hurricane-force winds? We call that January. This year has been unusually calm in that we didn't seen much over 100mph, but you get some years like that and you get some years where it doesn't go below 90mph for a week.
None of those have hit my region. That's all in the south of England, which is as geographically and climatically different as Florida is from Alaska.
... try not building your house in an area prone to hurricanes. Or, if you're going to do that, try not living in a house constructed along the same basic design as a plywood packing crate.
Most of the houses in the US would simply not be passed as fit for human habitation in the UK, because of their shoddy thin-crappy-wood-over-thin-crappy-frame construction.
Get the diesel one then. Petrol is obsolete. Why would you burden yourself with a gutless, thirsty, buzzy petrol engine?
If you have to rip apart walls - or even just skim them before you paint or paper - take the time to run in plenty of cabling. You can get audio and video baluns for running over CAT5 these days fairly cheaply, although the hifi purists will throw their hands up in horror.
CAT6 is cheap enough, might as well start ahead of the curve.
So, it's a Bad Thing that they speak Punjabi as a first language? And yes, if it was Welsh or Gaelic then it would be a great example of progressive education saving their heritage...
... although I wouldn't expect timmeh to know the difference.
I think you're rather missing the point. The fact that SDR *is* software-defined is what allows you to use an FIR filter.
What sort of hardware you implement this on is irrelevant. Even supposing you use a pair of ADCs hooked to an FPGA and implement the whole thing in the FPGA, it's still software.
Your old analogue mobile phone frequencies are in analogue TV frequencies in the rest of the world.
I break FCC regulations all day, every day. Why should I care about the "cell phone hole"?
In a conventional radio receiver, you start by filtering off the wanted signal with a broad filter, mixing it with another locally-generated signal (the Local Oscillator) to make a lower Intermediate Frequency (IF), then filtering the IF to extract a single "channel" of information. Then you demodulate this, possibly after mixing it down to an even lower IF.
In a software-defined radio, you convert directly down to a much lower frequency (audio frequency, even), but - and this is the clever bit - you do it with two local oscillators, 90 degrees out of phase. This gives you a complex sample, a pair of samples representing In-phase and Quadrature, or the real and imaginary components of your signal.
From there you can apply digital signal processing techniques to extract the wanted signal, show an FFT of the chunk of band you're capturing, and so on. This lets you do very sharp filtering, because you're no longer constrained by the physical realities of trying to implement electronic filters with practical components.
Shameless plug - if you want to try SDR out, go here:
https://github.com/gordonjcp/lysdr
Follow the instructions in the README, then either post a reply or bug me in irc.freenode.net ##electronics for further instructions.
If they want to break the speed limit, they can overtake. Fucked if I'm stopping to pull them out of the ditch when they crash, though.
Another great way to avoid getting speeding tickets is to not break the speed limit.