BEHIND the cash register at Smoke Shop No. 2 in downtown San Francisco, Sam Azar swipes a customer’s credit card to ring up Turkish cigarettes. The store’s card reader fails to scan the card’s magnetic strip. Azar swipes again, and again. No luck.
As customers begin to queue, he reaches beneath the counter for a black plastic bag. He wraps one layer of the plastic around the card and swipes it again. Success. The sale is rung up.
“I don’t know how it works, it just does,” says Mr. Azar, who learned the trick years ago from another clerk. Verifone, the company that makes the store’s card reader, would not confirm or deny that the plastic bag trick works. But it’s one of many low-tech fixes for high-tech failures that people without engineering degrees have discovered, often out of desperation, and shared.
Today’s shaky economy is likely to produce many more such tricks. “In postwar Japan, the economy wasn’t doing so great, so you couldn’t get everyday-use items like household cleaners,” says Lisa Katayama, author of “Urawaza,” a book named after the Japanese term for clever lifestyle tips and tricks. “So people looked for ways to do with what they had.”
Popular urawaza include picking up broken glass from the kitchen floor with a slice of bread, or placing houseplants on a water-soaked diaper to keep them watered during a vacation trip.
Today, Americans are finding their own tips and tricks for fixing misbehaving gadgets with supplies as simple as paper and adhesive tape. Some, like Mr. Azar’s plastic bag, are open to argument as to how they work, or whether they really work at all. But many tech home remedies can be explained by a little science.
Cellphone Losing Charge
If your cellphone loses its battery charge too quickly while idle in your pocket, part of the problem may be that your pocket is too warm.
“Cellphone batteries do indeed last a bit longer if kept cool,” says Isidor Buchanan, editor of the Battery University Web site. The 98.6-degree body heat of a human, transmitted through a cloth pocket to a cellphone inside, is enough to speed up chemical processes inside the phone’s battery. That makes it run down faster. To keep the phone cooler, carry it in your purse or on your belt.
This same method can be used to preserve your battery should you find yourself away from home without your charger. Turn off the phone and put it in the hotel refrigerator overnight to slow the battery’s natural tendency to lose its charge.
Remote Car Key
Suppose your remote car door opener does not have the range to reach your car across the parking lot. Hold the metal key part of your key fob against your chin, then push the unlock button. The trick turns your head into an antenna, says Tim Pozar, a Silicon Valley radio engineer.
Mr. Pozar explains, “You are capacitively coupling the fob to your head. With all the fluids in your head it ends up being a nice conductor. Not a great one, but it works.” Using your head can extend the key’s wireless range by a few car lengths.
Dry Ink Cartridge
If your printer’s ink cartridge runs dry near the end of an important print job, remove the cartridge and run a hair dryer on it for two to three minutes. Then place the cartridge back into the printer and try again while it is still warm.
“The heat from the hair dryer heats the thick ink, and helps it to flow through the tiny nozzles in the cartridge,” says Alex Cox, a software engineer in Seattle. “When the cartridge is almost dead, those nozzles are often nearly clogged with dried ink, so helping the ink to flow will let more ink out of the nozzles.” The hair dryer trick can squeeze a few more pages out of a cartridge after the printer declares it is empty.
Cellphone in the Toilet
It could happen to anyone: you dropped your cellphone in the toilet. Take the battery out immediately, to prevent electrical short circuits from frying your phone’s fragile internals. Then, wipe the phone gently with a towel, and shove it into a jar full of uncooked rice.
It works for the same reason you may keep few grains of rice in your salt shaker to keep the salt dry. Rice has a high chemical affinity for water — that means the molecules in the rice have a nearly magnetic attraction for water molecules, which will be soaked up into the rice rather than beading up inside the phone.
It is a low-tech version of the “Do Not Eat” desiccant packets that may have been packed in the box the phone came in, to keep moisture away from the circuitry during shipping and storage.
Longer Wi-Fi Reach
If your home Wi-Fi router doesn’t reach the other end of the house, don’t rush out to buy more wireless gear to stretch your network. Instead, build a six-inch-high passive radio wave reflector from kitchen items, like an aluminum cookie sheet.
Follow the instructions atfreeantennas.com/projects/template. Place the completed reflector — a small, curved piece of metal that reflects radio waves just like a satellite TV dish — behind your Wi-Fi router. It focuses the router’s energy in one direction — toward the other end of the house — rather than letting it dissipate its strength in a full circle. No cables, no batteries, no technical knowledge required. Yet it can easily double the range of your network.
You need to clean a skipping DVD or CD, but as a bachelor you don’t have any sissy cleaning fluids? Soak a washcloth with vodka or mouthwash.
Alcohol is a powerful solvent, perfectly capable of dissolving fingerprints and grime on the surface of a disc. A $5 bottle of Listerine in your medicine cabinet may do the job as effectively as a $75 bottle of DVD cleaning fluid. Also, swabbing your copy of “Lost Weekend” with Stoli instead of fussing with a Discwasher kit is a lot more manly.
Too Much Flash
If your cellphone’s built-in camera flash is much too bright, washing out photos, tape a small piece of paper over the flash. Experiment with different colors and thicknesses of paper to tone down the flash from superbright white to a more pleasing glow for evening photos.
Crashed Hard Drive
If — no, make that when — your PC’s hard drive crashes and can’t be read, don’t be too quick to throw it out. Stick it in the freezer overnight.
“The trick is a real and proven, albeit last resort, recovery technique for some kinds of otherwise-fatal hard-drive problems,” writes Fred Langa on his Windows Secrets Web site. Many hard drive failures are caused by worn parts that no longer align properly, making it impossible to read data from the drive. Lowering the drive’s temperature causes its metal and plastic internals to contract ever so slightly. Taking the drive out of the freezer, and returning it to room temperature can cause those parts to expand again.
That may help free up binding parts, Mr. Langa explains, or at least let a failing electrical component remain within specs long enough for you to recover your essential data.
That’s the spirit of folk remedies: They may or may not work, but what have you got to lose?