| Author | Views | Views Today | Rank | Comments |
| Dudley LeRoux | 20,537 | 53 | ![]() |
11 |
| This tester can be used to check the polarity of any power source, and is therefore very useful when installing automotive equipment, alarm systems or anything else you can think of. Because this circuit is so simple and cheap, even frying one with an over voltage is not a big deal. |
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| Excellent. Used it to sucessfully add more visible large additional turn indicator light above dash board on car. | ||
| thank u and many other good people on the web that share wat they make your polarity tester has made things eeser for me and works great thanks once again nick italy | ||
| Nice. However, you don't need all that rectifier! Do you? Only two, reverse parallel LEDs and resistor. So it gets even cheaper and easier to fit in a plastic pen. :-) |----------|<---------| o-----////-----| |-------------o |----------->|--------| | ||
| I'm looking for a polaraty tester that can read plus and mines this is to check a product when is plus or minus the unit should have to probes so when i touch it if going to tell if it can out plus or minus. | ||
| This circuit is true but i need more explanation please. | ||
| what is the probe | ||
| Found useful but why not be design to rate voltage in case the voltage is higher. | ||
| you crazy specify the uses! hello polarity tester duh | ||
| I had a simple tester with just a bulb and 2 wires connected to it. 1 red 1black. My grandson steped on it. Gone. This was a very handy tool for identifying the positive + wire so you wouldnt wire a device incorrectly or in reverse. The only time the bulb would lite is when the 2 wires were correctly identified. where can I find such an item? thank you for your time. | ||
| very useful allthough i used shokey diodes insted | ||
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