photo RSMAtnWebAdRed13.jpg

The Computer Corner


By Charles Miller

What to Do When the Plug Fit But Still Did Not Work

Recently I have received several unrelated calls with one thing in common. All the calls were from clients who were having troubles with things that plugged in and seemed to fit but for some reason did not work as expected.

The first call came from Jackie. She had noticed that her TimeMachine backup was not backing up her Mac as it should. A short investigation turned up that she had connected her new external hard disk to the computer using a USB cable that had come with a cell phone. Yes, the cord fit properly in the sockets, but, no, it did not work.

The fact is that not all USB cables are created equal. USB1 and USB2 cables usually have four wires: two are for data and two for 5 volts DC power. Copper for wires is expensive, so sometimes manufacturers will save themselves a fraction of a centavo by leaving out one pair of wires if not needed. The cable Jackie tried to use had the pair of wires for charging a cell phone with 5 volts DC but lacked the data pair, so when she connected it to her external hard disk, it could not transfer data. Yes, it fit, but, no, it did not work.

My friend Stuart ran into a situation in which the rechargeable batteries in his cordless phone would no longer charge. Since the AAA batteries were physically the same size as flashlight batteries, those are what he used. The phone worked, and everything seemed fine. I warned him, however, that the flashlight batteries were likely to explode when charged. “Explode” might not be the best choice of verb, because the explosion would not be as much as a kernel of popcorn, actually more like a Rice Krispie. But the explosion would release battery acid and might ruin a good cordless phone. So, yes it fit, and it even worked; but, no, using the wrong battery is a bad idea. That was apparently proven a few days later when the phone died, and although we may never be sure, probably because the rechargeable batteries were 1.2 volts while the flashlight batteries were 1.5 volts. The phone simply was not designed to withstand the higher voltage.

Then Susan had a chilly experience during one of our recent winter cold snaps. The desk where she used her computer is in one of the colder rooms in the house, and it could have been so much more comfortable to have a little more heat in there. The simple solution was to plug in an electric heater, and the closest available electrical outlet was one she saw on the surge protector and battery backup where her computer, printer, and modem were connected. The plug fit perfectly into the socket, but the problem was that the heater was rated at 2,500 watts while the label on the bottom of the surge protector said it was rated to a maximum of 400 watts. The computer, printer, and modem all survived, but a new hundred-dollar battery backup and surge protector was utterly destroyed. So, yes, the plug fit, but no, it did not work.

Charles Miller is a freelance computer consultant, a frequent visitor to San Miguel since 1981, and now practically a full-time resident. He may be contacted at 044 415 101 8528 or email FAQ8 (at)


Comments are closed

 photo RSMAtnWebAdRed13.jpg
 photo RSMAtnWebAdRed13.jpg

Photo Gallery

 photo RSMAtnWebAdRed13.jpg
Log in | Designed by Gabfire themes All original content on these pages is fingerprinted and certified by Digiprove