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Comment Re:A simpler cure (Score 1) 240

I'm envious too. I rarely sleep well.

I've never tested myself thoroughly but I think I'm about the same. Given the opportunity I'm not tired until 2 or 3 hours after my normal bedtime, so approx a 26 or 27 hour cycle. On weekends I'll let this wind out but it's a harsh reset on Sunday night to get back into the week's routine.

Comment Re:Why dealerships get a free ride (Score 1) 342

Bollocks.

Cars arent going to run out of parts after 5 years if a dealer stops stocking them. If there is a market for the parts then third party manufacturers will keep them coming for 20 years.

Dealerships stock some genuine parts at very large mark ups. There are plenty of other auto parts distributors that stock far more genuine and non-genuine spare parts and do so at a better price.

Comment Re:Secondhand smoke? (Score 1) 156

Half-face respirators. You know, the rubberised mask with the strap that goes over your head, with some canisters mounted either side. Eg like this: http://www.moldex.com/au/respi...

Anything less is just rubbish,, especially the disposable ones. They are too flimsy to hold a good seal in most situations and they only last an hour or so.

Comment Re:Whose phone is banned? (Score 1) 366

Because people talking ona phone are about 1000 times more annoying than a real conversation:
1) People often raise their voice when talking on a phone. CAN YOU HEAR ME NOW
2) Hearing half a conversation is distracting as your mind tries to fill in the blanks
3) HOW ABOUT NOW. CAN YOU HEAR ME NOW. YEAH I CAN HEAR YOU. YEAH IM ON A PLANE! YEAH THEY CHANGED THE RULES. I KNOW! HOW ABOUT THOSE KARDASHIANS??

Comment What I've learnt from automating my own home (Score 4, Interesting) 336

I've nearly gone as far as I can automating systems and devices my current home - temperature & humidity sensing in most rooms, motion sensing in every room, zoned ducted evaporative aircon, a couple of split reverse cycle aircons, z-wave lighting and exhaust fans, and mains power monitoring.

-- Lighting ---
Z-Wave works mostly well enough, and I use this to automatically turn on lights when motion is detected, turn off lights after a while with no motion, or turn off when I go to bed. Unfortunately the turn-on the signal can take up to several seconds on a large 1-wire network, so even when the motion sensor triggers quickly you can still be halfway across a room before the lights turn on which is a pain. On top of that, I cant disable the z-wave dimmer soft-on and soft-off feature which is a pain when you're trying to get quick response. For the turn off, it's probably not worth it since I upgraded to LED lights as the power saved is negligible.

At the price of parts + install being $150 - $200 per light fixture it's not really been worth. A few minor conveniences and a lot of annoyances. I think I'd be better off with no automation on most regular light fixtures, and just some inline z-wave switches on frestanding lamps and mood lighting. Maybe automation on the living room and master bedroom for convenience / scenes.

-- Temperature / Humidity ---
Temperature and humidity sensing in every room has been great. In Australia where I live it's quite uncommon to have a whole house climate control system, so I've used these to help come up with a automated strategy for every room that integrates the available air conditioning systems. Also I've used the temperature, humidity and (calculated) air speed in each room to create a "feels like" temperature. Controlling against this rather than the dry air temp has given a much better result.

I've been using 1-wire devices as sensors, which need 1 or 2 twisted pairs for comms and power - cat5 is great. The DS18B20 temperature sensors are very cheap, have been very reliable and can send signals over long distances. Unfortunately the DS2438 based humidity sensors are not as good and I've had to partition the network a 1-Wire hub. Currently I still have intermittent errors with just 30m of cable on each DS2438 leg, whereas the DS18B20 temperature sensors could cope with a load of 100m plus. If I was building a new house I'm not sure if I'd use them again due to the issues with humidity sensing, but I'm not convinced there's many other affordable alternatives either. For reference the DS18B20 sensors are costing me about $2 each, and the DS2438 based humidity sensors (using a Honeywell humidity IC) are about $20 each from parts. Since I work as a control engineer, my next preferred option would be modbus slave devices over RS485.

-- Air conditioning ---
For the split reverse cycle aircons I used a central GlobalCache IP2IR infrared blaster, and then ran long wires with a concealed IR emmitter fitted inside the aircon head units. This works fine but the IR programming for air conditioners is painful. I wish there was an automation interface standard for them.

For the ducted aircon I had to integrate the zone controller using an arduino for digital IO, communicating back to the central server via RS232 serial (over cat5). I upgraded the fan to use a VFD (variable frequency drive) and this can be controlled directly over RS485 using MODBUS RTU.

-- Conclusion --
If I had my chance again I'd probably just run multiple cat5e or cat6 to every room
  - 2 to 4 at floor level for computers and TV's
  - 1 or 2 behind the light switches for potential CBUS or other wired lighting control systems. These would be wired to a seperate patch panel
  - 1 or 2 behind a wall mounted sensor enclosure - this could then have both a temp/humidity sensor and IR emitter fitted. These would also be wired to a seperate patch panel

Ideally I wouldnt run any mains power to wall light switches - all of the switching would happen over serial comms or low voltage IO (using the cat5) and then the mains switching can happen centrally - either dumb relays, a PLC or CBUS controller.

The above setup would then make interconnect and automation via either Ethernet or serial (RS485) easy, both of which are reliable and well supported protocols. RS485 doesnt get much attention in home markets but it's still huge in industry and commercial installs.

Comment Re:Bravo, Tesla (Score 1) 195

I can think of one easy way - measure the no-load AC voltage as a baseline, then continue measuring the voltage as the current is increased. If the voltage drop is beyond a certain tolerance then that means there is some series resistance in the wiring somewhere and this is indicative of undersized wiring or poor junctions.

Comment Install an alarm panel without central moniting (Score 1) 248

Just about any standard security panel will have dialer options, which can then phone your mobile if there is a break in. Just fill your house with standard PIR motion detectors, and some nice loud sirens (inside) near your valuables so that it drives the thieves crazy. You can even go wireless these days to save on install fees, but I like the reliability of wired.

There's lots of bands to chose from but I went with DSC (the PC1832 model - http://www.dsc.com/index.php?n=Products&o=view&id=2) because they are regularly used by commercial installers. They are well priced and available on Ebay, and any technically minded person should have no problem installing it themselves. This on it's own should be enough to make thieves move on to an easier target.

For video surveillance then Zoneminder is an easy choice and works a treat. Also the DSC panels support a PC serial interface module so between Zoneminder and some scripting (or a home automation platform like homeseer) you can have a comprehensive monitored system that records incidents and can do something smarter about them.

Comment Re:who benefits (Score 2) 118

As much as I agree that having both heads of the family to work sucks, we have a much better standard of living now than 30 years ago.

For example we now have:
  Two or more cars per family
  Clothes driers and dishwashers
  Food processors, breadmakers & microwave ovens in addition to normal oven/cooktops
  Reverse cycle air conditioners is multiple rooms of the house
  Mobile communication & internet devices in everyone's pocket
  Multiple TV's and computers thoughout the house

All of these things would have been considered luxuries 30 years ago and are now commonly affordable.

Comment Don't Tell Mom I Work on the Rigs (Score 2) 796

Don't Tell Mom I Work on the Rigs: She Thinks I'm a Piano Player in a Whorehouse - http://www.amazon.com/Dont-Tell-Mom-Work-Rigs/dp/1600940250

Hilarious laugh out loud story of a guy that grew up in country Western Australia and went on to work in some of the most extreme locations on the planet. He's a fantastic story teller and it's a great read.

Comment Re:assuming plutonium-238 is true (Score 5, Informative) 268

The radioactives used in RTG's are usually alpha emmitters that can be sheilded very easily - thin sheet metal is enough, let alone the whole carrier assembly. It's gamma rays that are the problem and require several feet of lead to shield fully. Chosing the right isotopes with a favourable decay chain reduces or eliminates gamma ray production.

See http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#Selection_of_isotopes

Comment Re:Why not batteries (Score 2) 296

Maybe where you live but in Australia we get charged 24c/kWh consumption and get paid 7c/kWh when we feed back to the grid.

To help this situation some state governments intriduced a feed-in tarrif that supplemented homeowners by up to 40c/kWh (yay!!), but this program had a limited number of places. For those lucky enough go get a spot it was supposed to be guaranteed for 10 years but the buggers just tried to cancel the program after 2, with huge public backlash.

Comment Re:Pragmatic choice (Score 1) 229

You, sir, are an idiot.

The FTTH GPON was going to be deployed as 2.48Gbit downstream and 1.24Gbit upstream, servivcing 32 users. The contention ratios and upstream capabilities are freaking awesome.

By comparison the cheap FTTN proposal is being designed with 2GBit backhaul servicing 200 users. This sucks. Now, even if they upgraded to 2 x 10G fibres, you are still heavily limited in your upstream bandwidth by the nature of VDSL - all of those signal converging together cause significant co-interference.

Finally, I'd like to see how a "simple copper can do 1Gb" in any real world conditions. Good quality Cat5E can 1GB over 4 pairs (not a single pair), and only for 100M. When you start looking at single pairs of shitty corroded cable low diameter cable, bundled together in groups of 100, all co-interfereing, and having to travel 500M to 1km, it's a completely different story.

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