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Comment Re:GPS is just an aid (Score 1) 366

Was walking in an old city I had never been to before with wife (she lived there many years), and she was perplexed when I said she was going the wrong way. How do you know she asks... Just look town: single stone path for local paths, two stones for local roads, three for major roads, four for arteries into the city core, and five for the main street.

(Thanks, Mr. Klein-- 10th grade history!)

Comment Re:Surges weren't my biggest problem... (Score 2) 137

Yes. In the course of a day, mains power where I used to live would range from 100V to 300V. You get the prolonged over voltages when a large load drops off, either a circuit breaker trip, or something more random. Modern voltage regulators prevent this, but legacy units will operate for a few minutes at 30-50% over voltage.

Even with modern voltage regulators, when the load is random they are often programmed pretty loosely. 3rd world load creates 3rd world grids.

Comment Surges weren't my biggest problem... (Score 2) 137

Persistent over/under voltage was always my challenge traveling. A surge protective device doesn't do anything when power is running at 300V for a few seconds. The old MOVs, without proper fusing, would always pop and start smoking, which was a sign to trip the main breaker before everything got fried.

For truly sensitive electronics we always used commodity 12V chargers tied to a big battery bank with individual inverters for each piece of equipment. We might have had a custom filter to deal with ripple current off the chargers, too long ago to remember the details. The chargers lasted 2-3 months on average, but were easy to replace. Normal dual-conversion UPSs would barely last 3-4 months and were much harder to find and more expensive.

For today, I would have two laptop power supplies and an extra battery, and only charge from USB. The bigger USB power supplies are pretty robust, worth carrying extras.

Comment Re:You must be new here (Score 1) 1833

Not always true. In a perfect world, modding helps manage and focus the discussion. Disagreeing is a valid mod when the statement being made is not contributing to the discussion. I generally go for overrated in these cases, since it doesn't impact karma; it serves a purpose.

I would argue that not posting anything when you don't really have something worthwhile to say is more valuable: moderate thyself first.

My hope for Slashdot: provide more content that fosters strong discussion in a variety of topics that are relevant to today's nerds. Try to keep editorial agendas to a minimum, and keep the useless kruft from being forced on everyone.

Comment Re:Why not a roof? (Score 1) 407

Poles generally don't have high enough wind loading; you need a grid to achieve that.

I imagine you could make ~100' wide x 700-1,000' trusses periodically along the road with 500-750kW inverters and make something work, but the challenge is getting it up high enough, and protecting the columns from car crashes.

Comment Firewall (Score 1) 261

Personally trying to set up a Ubiquity EdgeRouter to do the same. In my case, there are just a few devices I don't want to have any external access, so I will have a dedicated SSID for them and provide local network access but no routing. Other things I will have to manually switch a network port for a device to give access to the Internet.

Haven't hit the point yet where I feel a need to do a transparent proxy; my goal is mainly to strip "cloud" functionality off devices that I don't want to have it.

Try too hard though, and you will drive yourself batty.

(For the iPhone, I use 1-Blocker. It does a pretty good job, but far from perfect.)

Comment Re:Why not a roof? (Score 2) 407

That was my first reaction as well, but a roof structure would run about $4-5/watt for the system, with panels about 35% of the cost.

Assuming the roadway is about half the efficiency at peak output, cars traveling at 60mph and keeping 6 car lengths minimum between themselves, twice the cell cost but no superstructure... Your installed cost per watt is 70%, with a 15% performance penalty, or a pro-rata $3.3/W.

Granted upkeep will be higher, and life likely lower, but might actually work.

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