What you need to know to safely replace or substitute AC adapters

AC adapters inevitably break or get lost. That means you have to replace them to get your devices working again. But a lot of people don’t know how to do that safely. Here’s what you need to know when you need to substitute AC adapters.

This is important. Getting it wrong can damage your equipment, the adapter, or both. The damage can be immediate, or it can appear over time.

The specifications for your AC adapter (also not affectionately known as wall warts or power bricks) should be printed on the old one, and hopefully on the device too. If you lost the adapter and the specs aren’t on the device, try a web search on “ac adapter specifications” and the name of the product.

It used to be you could take the device to Radio Shack, and $25 and five minutes later you had a good replacement. Today you might try Batteries Plus for a similar experience. But if you’re willing to do the legwork yourself, often you can find a close-enough match for closer to $10.

So, with all that said, here are the handful of things you need to know when you’re shopping for an AC adapter. The specifications don’t have to match exactly, but you have to know when you can cheat and when you can’t. Read more

Save energy and money with smart power strips

I stumbled across this money-saving tip today. A company called Bits Limited sells “smart” power strips. Here’s how they work: You plug a device into one of the plugs, and when you turn that device on, it switches power on to other outlets. The strip also figures out how much energy the device uses when it’s off, so when it senses you’ve turned that device off, it cuts power to those other outlets.

Here’s an obvious use: Plug your TV into the master outlet, then plug your VCR, DVD player, cable box (or powered antenna if you’re a cable-hating tightwad like me) into the autoswitching outlets.The reason these strips work is because most home appliances use power even when they’re switched off. A powered-off TV uses power because part of it has to stay on all the time waiting for you to hit the power button on your remote. The same thing is true of your DVD player, VCR, and anything else that has a remote. Any device that uses a plug-in “wall wart” transformer is also consuming power. The transformer chews up a watt or two even if the device it powers is turned off.

So if you can bring yourself to walk over to the TV to turn it on rather than using the remote, you can buy the cheapest $31 model for each TV in your house and plug your stuff into that. (To save more money, check for refurbs.)

The manufacturer states one of these devices can save you $11.55 a month, on average, when used with a computer.

The savings won’t be as high with other devices like TVs, but you can expect to save a few dollars and in the summer, you’ll save slightly more because those devices won’t be generating excess heat that your air conditioner has to dissipate. Each strip you buy should pay for itself in less than a year.

Plus, those wall warts will last longer if power is cut to them when they aren’t in use. I’ve come across numerous “broken” old-school video game machines whose only problem was a burned-out wall wart. Replacements can be pricey ($10-$20), so if these power strips save you from having to replace two of those over the lifetime of the unit, they pay for themselves right there.

The company also sells beefier units with more outlets and more protection intended for computers. The idea there is you can plug the computer in, and when you turn your computer off, it will automatically shut off your monitor, printer, and any other peripherals you have in order to save power.

I have mixed feelings on using these with computers. From an energy consumption standpoint, having a computer powered on all the time is comparable to having the lights on in the room all the time–and we’re talking old-fashioned incandescents here, not CFLs. So plugging your computer into one of these devices and turning it off when you’re not using it would save a lot of power. While computer monitors should be turned off when not in use, there’s nothing worse for the computer itself than turning it off and on repeatedly. I leave my computers on all the time, and in the last 10 years, I’ve had two hardware failures. One was a hard drive crash in a laptop (very difficult to avoid), and the other was a dead power supply in an HP Pavillion desktop after a power failure. As underpowered as that power supply was, that failure probably was inevitable too. Two failures in 10 years is a pretty good record.

Electricity is expensive, but computer failures are expensive too. I prefer to leave my computers on, save power where I can (I own several computers but they all only print to one printer, for example), and maximize my computers’ life expectancy.

I’m thinking very seriously about at least ordering one of these for the living-room television. It won’t pay for itself as quickly as the programmable thermostat did, but they only cost about $5-$10 more than a traditional power strip with comparable protection ratings. If I look at them as a $10 investment instead of a $30 investment, they’ll pay for themselves pretty fast.

I did go looking for other manufacturers. It appears that Fellowes made these in the past but has discontinued them. For now, it appears Bits Ltd’s offerings are the easiest ones to find. It would be nice if that changed.

A crude way to get some of the benefit of these is to use an electrical outlet timer. Plug the timer into the wall, plug your power strip into the timer (assuming the timer has a grounded outlet), then set the timer to cut the power off at night. The savings won’t be as dramatic, but if you happen to have a timer or two around the house to control Christmas lights, you might as well put them to use saving you some money during the other 10 months of the year.

CompUSA’s $30 house-brand router looks like a rare bargain

I just built a network for a friend using CompUSA’s $30 cable/DSL router/4-port switch. I’m not sure if the price was a Memorial Day special, or if that’s the regular price. Considering you can’t get a Linksys or D-Link for under $50 without rebate hassles, and usually they cost closer to $80, that’s a nice deal.
The CompUSA unit looks bland and generic–it’s brown and boxy, from the same design school as the original Commodore 64–but that’s the only knock I have on it. Hide it behind your desk if its homely looks bother you. Installing it was literally a plug-in-and-go affair. Plug in the cable modem, plug in the computers, release the computers’ IP addresses and renew them (or reboot if you wish), and they’re all on the network.

If you want to get fancy, then open the manual. You can do port forwarding, set up a DMZ, and do everything else you’d expect from a consumer router. It even includes dynamic DNS support–something the more expensive units didn’t give you, the last I checked.

I can’t speak for the long-term reliability of the unit, since I literally spent 15 minutes with it. The price is good enough that to me, it’s worth a slight risk. In devices like this, it’s the wall wart that’s most likely to fail anyway.

So if you or a friend is looking to share your cable or DSL broadband connection and there’s a CompUSA nearby, it’s worth a look.

Replacing wall warts with PC power supplies

I wrote a long, long time ago about my adventures trying to find a wall wart for my old 8-port Netgear dual-speed hub. The other day I stumbled across a novel idea for a replacement.
I won’t rehash how you determine whether a unit is a suitable replacement–read the above link if you’re curious–but suffice it to say a $5 universal adapter from Kmart is fine for my answering machine or my cordless phone and can probably provide the 5 volts my Netgear needs, but my Netgear also needs 3 amps and the universal adapter I keep around can only deliver 20% of that. The beefiest 5v unit I could find at Radio Shack could only deliver 1.5 amps.

A PC power supply delivers 5V and 12V on its hard drive connectors. And PC power supplies deliver plenty of amperage: one of mine will deliver 25 amps on its 5V line, and 10 amps on its 12V line.

In a pinch, I could just obtain a suitable plug barrel that fits my Netgear from Radio Shack, clip the power connector off a dead CPU fan, and solder the plug to the red wire (5 volts) and a black wire (ground), put it in a PC, and use that to run my Netgear hub. The increased power draw would be equivalent to putting three typical PCI cards in the system. Just be sure to wire things right–reverse polarity can kill some devices.

Rather than using one of the PCs I actually use, it would be better to obtain a cheap microATX case, short the green and one of the black wires on the 20-pin motherboard connector with a paper clip, insulate the paper clip with electrical tape, and then wire things up to the drive connectors. Or, for that matter, you could use some of the other leads available on the 20-pin connector if you have a device that needs 3.3 volts (pinout here.) You could also just use a bare ATX power supply with a paper clip connecting the green wire and one of the black wires on the 20-pin motherboard connector, if you’re into the ghetto look.

An AT power supply would also work and it offers the advantage of being really cheap and common (here’s a nice writeup about an AT power supply’s capabilities), but most AT boxes require you to hook up enough 5-volt devices to chew up about 20% of its rating on that power rail before they’ll power up. I have a 200-watt AT power supply that delivers 20 amps on its 5-volt rail, so my 3-watt Netgear hub probably wouldn’t be quite enough on its own. So it might be necessary to either connect an obsolete motherboard to the power supply or connect a 1-ohm resistor between a +5 lead and ground, if you don’t have a plethora of power-hungry 5-volt devices to plug in.

But PC power supplies provide a cheap and commonly available way to replace odd wall warts, or at the very least, to reduce the clutter around the computer room.

Testing a blown AC adapter

All too often, people plug the wrong AC adapter into an electronic device. People just plug in the first adapter that fits, and usually when they do this, if the equipment wasn’t blown before, it is now.
They’re known by many names, most of them not affectionate: power bricks, wall warts… But you miss them when they’re gone.
Read more

Airshows, photography and Linux routing

Gatermann and I went out shooting again yesterday. More exploration of the warehouse district, and we found out that the warehouse district is a halfway decent place to watch an airshow. A couple of cargo planes buzzed us, tipping us off to what was going on, so I went chasing. I’m not the airplane junkie my dad was (few people are), but I’m still a sucker for exotic military planes. I borrowed Gatermann’s telephoto lens and took shots as planes went by. A pair of vintage P-51 Mustangs zoomed by, so I got a few shots of those. A couple of modern fighters made a brief appearance, but I couldn’t get them into the lens quickly enough to identify them. Chances are they were F-16s; not as common a sight as they once were, but you still see them.
I was hoping for a chance to see the Stealth Bomber; about four years ago I was in St. Louis on the 4th and as Gatermann and I were stepping outside to go get something to eat, we heard a low rumble overhead, looked up, and got a spectacular view of the rarely seen and highly classified B-2. Of course there wasn’t a camera in sight so we didn’t get a shot.

This year, a B-52 came from out of nowhere. It was huge–I mean HUGE–and very obviously not an airliner. I’d never seen one in person before so I didn’t identify it immediately. I got it in the camera, zoomed in on it, and figured out what it was. I got several shots. The B-52 is an oldie but a goodie; we used it heavily in Vietnam and in the late 1970s we intended to replace it with the B-1. Carter cancelled the B-1; later Reagan re-initiated it, but it was a disappointment. The B-1 never fully replaced the B-52 and now there’s talk of decommissioning the B-1 completely.

The B-52 was followed by a series of stunt pilots. I guess that’s good for oohs and ahhs, but I wanted to see weird airplanes.

The grand finale was the B-1. It totally snuck up on me; I think Gatermann spotted the thing first. I recognized it but the camera couldn’t catch it–the autofocus wasn’t fast enough. I switched to manual focus and waited. And waited. I spotted it looping around on the east side of the river; most non-classified stuff makes two passes. But you can’t get a good shot from that distance with this lens. I never saw it come back. It didn’t really look like it was landing (Scott Air Force base is across the Mississippi River, in Illinois), but I couldn’t find the thing. I gave up, turned around, and started walking back when Tom yelled and pointed. I quickly turned around, and the B-1 was just barely in range. I pointed and shot as it disappeared behind a warehouse. I think I got it.

I shot more than a full roll of just airplanes.

After airplanes and lunch, we headed out to CompUSA. Gatermann wanted a KVM switch; I wanted Baseball Mogul 2002. A Belkin 4-port switch was $200. A Linksys was $150. Gatermann grabbed the Linksys. I came up empty on Baseball Mogul. We went back to his place, hooked up the Linksys, and it was a real disappointment. It doesn’t pass the third mouse button. Numlock doesn’t work. And it has a slight ghosting effect on the picture. I didn’t notice it but Gatermann did. Stepping the resolution down and lowering the refresh rate didn’t help a whole lot. He’ll be taking the Linksys back. (To Linksys’ credit, the box is made in Taiwan, though its wall wart is made in Red China. I’m not a fan of financing World War III, nor am I a fan of slave labor, so I try to avoid products made in Red China whenever possible. Gatermann does too. I’m not sure what his reasons are but Red China’s treatment of the seven prisoners of war after their pilot kamikazeed our spyplane probably has something to do with it.)

Bottom line: Belkin’s KVM switches are better. I like the Linksys’ metal case better than the plastic case on my Belkin, but the Belkin performs a lot better and its buttons feel more solid. I also like the ability to change displays from the keyboard, rather than having to reach over to the switch like the Linksys requires.

I’m generally not impressed with Linksys’ products. Their DSL router, though it looks really slick, doesn’t forward ports very well. If you just want to split off a cable or DSL connection, it’s great. If you want to learn how the Internet works and run some servers behind your firewall, it’s going to frustrate you. It’s just not as stable as Gatermann’s Pentium-75 running Freesco, which we cobbled together from a bunch of spare parts. Get a used Pentium-75 motherboard with 8 megs of RAM, put it in a $20 AT case along with a $15 floppy drive and a pair of $15 PCI NICs and download Freesco, and you have something much more versatile and reliable for half the price. And a lot of us have most of that stuff laying around already.

And Linksys network cards are absolute junk. Their workmanship isn’t good, their drivers aren’t stable, and the cards have a tendency to just die. Or they age really poorly, spitting out tons and tons of bad packets as they carry out their wretched lives. Netgears are much better, and not much more expensive.

I also gave Gatermann’s Linux configurations a look. Freesco didn’t appear to be forwarding port 80, even though we configured it to, and Apache was installed and I’d verified it was working by opening a browser and going to I tried a variety of things–including forwarding the ports manually from a command line, using the ipportfw command if I remember right–but it never worked. Finally, I tried hitting the Web server from a Windows PC inside Gatermann’s private network. It was denied too. Workstation-oriented Linux distros tend to come locked down really tight by default these days, which is probably a good thing in general, but it makes it really hard to just turn on Web services to the world. I know it can be done but I wouldn’t know where to begin. So I had him download TurboLinux Server 6.5, which will probably solve all his web serving problems.

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