Testing Diode-The Accurate Way on How to Test Semiconductor Diode Using Multimeter

Written by Jestine Yong

Continued from page 1

The real problem when checking a diode usingrepparttar diode test function of a digital meter is that an open or leaky diode,repparttar 142879 meter sometimes reads ok(0.6). This is due to digital meter diode test output voltage (which you can measurerepparttar 142880 output test probe using another meter) is around 500mv to 2v. An analog meter set to x1 ohms have output about 3V(rememberrepparttar 142881 two 1.5V battery you installed inrepparttar 142882 meter!). The 3V voltage is enough to show yourepparttar 142883 accurate reading of a diode when under test.

Even if you have a good reading at x1 ohms doesn't mean thatrepparttar 142884 diode is good . You now have to set your meter to x10K to testrepparttar 142885 diode again. The output voltage of x10k ohms is about 12V(rememberrepparttar 142886 9v battery in your meter-1.5v+1.5v+9v=12v). Againrepparttar 142887 diode under test should show only one reading. This is exception to Schottky diode where it have two readings but not shorted reading. Ifrepparttar 142888 meter showed one reading thenrepparttar 142889 diode under test is good. If it has two readings then most probablyrepparttar 142890 diode is either shorted or leaky. The digital meter can't test it becauserepparttar 142891 output fromrepparttar 142892 meter is only 500mv to 2V.

If a diode breakdown when under full operating voltage, there is no way to testing diode (unless you have a very expensive diode checker which specially designed to locate this type of problem).Substituting with a known good diode is oftenrepparttar 142893 only way to prove that an intermittent diode is causing a particular problem. Sometimes an intermittent diode could be locate using a coolant spray.

Caution: Be certain that power is removed from any circuit before performing any ofrepparttar 142894 following diode checks, otherwise meter or circuit damage could result.

Conclusion-In order to correctly test diode function you need to setrepparttar 142895 analog meter to x1 ohms and x10K ohms range.

Jestine Yong is a electronic repairer and a writer. For more electronic repair information please visit his website at http://www.noahtec.com/electronic-repair-articles.htm

Spy Vs Spy Vs Spy

Written by Luigi Di Serio

Continued from page 1

Out came SpyCop (http://www.spycop.org) and Raytown Corp’s Anti Keylogger, then later PrivacyKeyboard (http://www.privacykeyboard.com). These are still some ofrepparttar best available. SpyCop scans a database of keyloggers definitions that is constantly updated, much like anti virus programs do. PrivacyKeyboard is a little different. It claims to simply blockrepparttar 142878 one and only method that keyloggers and screen shot recorders can use to capture data. Nevertheless, these programs really do work in their quest to block and weed out spy programs.

Today there are many generic brands of spy removers, dubbed “anti-spyware” programs. They do detect keyloggers, but also can scan for adware and other Trojans, pests, dangerous scripts and worms. Anti-spyware products are effective, but generally cannot block all keyloggers.

More dangers inrepparttar 142879 spy market Some marketers disguise their spyware products as anti-spyware to get even more confidential information from targets. They also give false-positive readings on their supposedly “free spyware scans” to convert fasters sales. Generally I would advise steering clear of those heavily advertised products that have nothing more than a one-page ad for their product.

Another thing to look out for? Keyloggers have now gone remote. Imagine you remote controlling a PC and monitor it from afar? Well with RemoteSpy (http://www.remotespyware.com), Spytech Realtime Spy (http://www.spytech-realtime-spy.com), I SpyNow (http://www.i-spyware.com) Smart Keylogger (http://www.smart-keylogger.com) and other programs you can! They send out as a Trojan-type file to monitor a computer. You do not even need access torepparttar 142880 machine. These products can be stopped with a good anti-spyware product, but once there on your PC they become hard to remove. This is especially true with Realtime Spy and SpyAgent because they are equipped with anti-spyware disable features. SaveKeys Undetecable by Alpine Snow (http://www.alpinesnow.com) claims to be impossible to detect by anti-keyloggers and anti-spyware programs.

So it is no longer spy vs. spy, but spy vs. spy vs. spy! Who knows what they’ll think of next? One thing is certain: This keylogger vs. spy software saga will continue for a long time, since these programs are now as common as firewalls and anti-virus.

Bad Spy Vs. Good Spy This is important. Most “Anti Spy” software sucks. Most just delete cookies, a few common keyloggers and pests, and are made by flash-in-the-pan companies that can’t afford to make updates as new threats arise. These “anti-spy” programs are simply sold as marketing gimmicks to scare people into believe they are “being spied on” to make quick coin.

There are good products, however, but be sure to do a lot of research before buying anti-spyware software. Most spy software is decent, user-friendly and useful… The problem is that they are fairly easy to catch. Choose a program like NetVizor (http://www.spytech-netvizor.com) or Net Spy Pro (http://www.system-spy.com) if you are running a business and want to monitor for security reasons. If want to monitor your kids, use NetNanny or IamBigBorther (http://www.parentalspy.com), which are parental monitoring tools.

Be careful using spy software, as it is now illegal and considered espionage to spy on competitors or on computers you do not own or administrate. Only time will tell whatrepparttar 142881 spy software marketplace will evolve into, but for now it appears that developers will keep updating anti spyware programs to combat spyware and spyware will continue to tweak and morph itself to hide from anti-spyware. I surmise this will continue until some sort of strong legislation or court precedence clearly outlaws one orrepparttar 142882 other. But until then… spy and spy-ers beware!

Luigi Di Serio is the owner of Top Secret Software one of the largest security and spy software retailers on the web.

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