Nuts and Volts - November 2014

In this column, Tim answers questions about all aspects of electronics, including computer hardware, software, circuits, electronic theory, troubleshooting, and anything else of interest to the hobbyist. Feel free to participate with your questions, comments, or suggestions. Send all questions and comments to: Q&A@nutsvolts.com

8 November 2014

■ WITH TIM BROWN Q & A

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magazine/article/november2014_QA.

• Broken Laptop

• VCR Eats Tapes

• Sound System Hum Broken Laptop

QI'm sad! My laptop went bad on me! I’ve never worked on one before, so my hope is that I can fix it with your help. It turns on and that is good. It comes on saying "Waiting for Windows," the mouse appears, then Waiting for Windows disappears.

However, the mouse stays on the screen. What is that telling me? It's an old computer and I hear that laptops are not great to work on. If I had a clue what to look for, it would be interesting to try. Thanks.

— Frank G.

AAll may not be lost. There are a couple of possibilities: a virus or the hard drive's "boot record" has been corrupted. The solution to both problems is similar. First, on the Start Menu, open the Run option and type in CMD to bring up the DOS Command Prompt (CP). [There is not enough room in Q&A for a full discussion of how to use the Command Prompt, so look on the Internet at websites such as http://dosprompt.info for more information.] In the CP box, you will see the Command Line C:\>; enter the commands here.

First, use the command CHKDSK/f/r to check the disk for bad sectors, recover readable files, and fix errors on the disk. If the laptop still will not boot, enter DIR in the CP and see if you can find any files that can be saved.

Keep any files you want by using the command COPY to save these files to another location (CD-ROM drive or external hard drive attached to the USB port or serial port). Be sure the files are saved on the new medium before proceeding.

The laptop either came with a startup disk (sometimes called a recovery disk), so insert the disk, boot the computer, and follow the instructions on the screen to reload the operating system onto the hard drive. If this doesn't work, the hard drive may need to be replaced which can be a hassle. You will need to get the manufacturer's instructions on how to open up the laptop and replace the drive (each laptop is different).

NOTE: If the laptop is really old and you have no files on it worth saving, you may want to buy a newer laptop (I am still using a 2003 PC and am on my third hard drive).

I cannot overemphasize that you save your computer files (laptop or PC) to an external device so that you don't lose valuable data in the event of a hard drive crash. I learned years ago to save my files often in case of a power failure (I realize most software already does this, but there’s no harm in being extra cautious).

VCR "Eats" Tapes

QI have a VCR that has developed a problem of "eating" the tapes. I turn on the VCR, insert the tape, and press Play. After a few seconds, the VCR powers down, and when I turn the power back on the tape is stuck. Pulling on the tape to remove it results in a broken tape. I have a large collection of video cassettes and converting them to DVD format would be too expensive. What can I do?

— John D.

AA video cassette recorder (VCR) is a fairly complex electro-mechanical device consisting of a tape drive system, video drum with record/playback head, electronic controls, and sensors — all of which must operate synchronously to play the video tape housed in the cassette (early TV station video tapes were unwieldy reel-to-reel affairs which were NOT feasible for consumer use and were difficult enough for the station engineers).

We bought our first VCR in the mid ‘80s for approx $750 and it lasted about 15 years. We bought two VCRs in the early 2000s for about $350 (grandkids needed a separate TV), and they have lasted over 10 years (the last one finally gave up the ghost this year). Currently, VCRs can be bought for as low as $80.

As far as repairing any consumer electronic device, one rule I follow is if it is over five years old, you probably will not be able to find replacement components. Add to that the fact that most devices today have OEM chips — ICs that can ONLY be obtained from the manufacturer who makes more profit from selling new devices than repair parts — plus, the time and effort you expend on finding manuals (in the "old" days, they came with the device) for troubleshooting and repair.