Meter Output Coupler

Campbellhausfeld .25in. Automotive Coupler MP3236 $25.83 Coupler

Coupler $29.99 Tomco Super Coupler 1/4 male NPT

Campbellhausfeld .25in. IM Industrial Style Coupler MP3234 $24.61 Coupler

Campbellhausfeld .25in. NPTM Universal Coupler MP3336 $24.88 Coupler

Campbellhausfeld .25in. Series Universal Coupler MP3335 $25.16 Coupler

Zurn Pexqest 1in. X .75in. Poly Coupler QQPC54XPK1 $21.63 Coupler

COUPLER 3-4mm $3 COUPLER 3-4mm

XLR Coupler $4.99 XLR Coupler

Super Talent Network Coupler Coupler $5.09 Super Talent Network Coupler Coupler

Vernier Sound Level Meter $179.99 MODEL- SLMBTA VENDOR- VERNIER SOFTWARE FEATURES- Vernier Sound Level Meter Many teachers have asked for a way to collect sound levels in decibels. Vernier's newest sensor, the Sound Level Meter, makes this possible. The Sound Level Meter has an output port so that it can be connected to any of our interfaces. The input range of the sensor is 30 dB to 130 dB. The Sound Level Meter also has an LCD display, which allows you to use it as a stand-alone device. * You can collect sound level data in many real-world situations: * Before, during and after a concert or dance. * Throughout the day in a school hallway or shopping mall. * Judge cheering contests at pep rallies. * Outside and inside a car equipped with a stereo system. * Make and test a model of an ear and ear canal. -- SPECIFICATIONs ------------------------------------ RANGE - 30-130 dB ACCURACY - 1.6% at 94 dB FREQUENCY RESPONSE- 31.5 to 8000 Hz www.vernier.com

Neutrik NYS237 1/4 Inch TS Male to Male Mono Coupler $2.8 Superb for connecting a couple of pedals that from the same manufacturer or have the input and output located in the same position, this Neutrik 1/4 inch TS male to male adapter serves as both a pedal connector or a mono cable coupler.

Auto Meter Sport-Comp Electric Ampmeter Gauge $73.99 Short sweep electric amp meter gauge. Use only on alternators with maximum output of 60 amps. Must be installed by experienced mechanic.

Auto Meter Traditional Chrome Electric Ampmeter Gauge $50.99 Short sweep electric amp meter gauge. Use only on alternators with maximum output of 60 amps. Must be installed by experienced mechanic.

Cable Coupler $26.94 Cable Coupler Cable coupler, marine network

In-line Coupler - phone coupler $2.99 C2G In-line Coupler - Phone coupler - RJ-11 (F) - RJ-11 (F) - ivory

In-Line Coupler phone coupler $1.99 Tripp Lite In-Line Coupler - Phone coupler - RJ-11 (F) - RJ-11 (F)

7-Range Sound and Noise Meter $21.6 - Seven sound-level ranges:allow measurements from 50---126 DB.- A and C weightings:lets you check compliance with safety regulations as well as make acoustic analysis.- Slow and fast response settings:let you check peak and average noise levels.- Builtin battery condition indicator.- Phono-type output jack:for connection to home theater or test equipment.- Threaded insert:lets you attach the meter to a camera tripod for increased accuracy. 60 dB: 50 TO 66 dB 70 dB: 60 TO 76 dB 80 dB: 70 to 86 dB 90 dB: 80 to 96 dB 100 dB: 90 to 106 dB 110 dB: 100 to 116 dB 120 dB: 110 to 126 dB- Accuracy: +/- 2 dB @ 114 dB- Standard: 0 dB = 0.0002 u bar- Signal Output: 1.0 volt (peak) minimum into open circuit,with full - scale meter deflection at 1 kHz- Load Impedance: 10 kOhms minimum- Distortion: Less than 2% at 1 kHz, 0.5-volt- Microphone: Electric condenser; omnidirectional

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2.45 GHz Magnetron to Coax Experiment

Some Basic Concepts of Fiber Optic Loss Testing

When testing loss in a fiber optic link, some basic principles must be kept in mind all the time.

1. The testing wavelength should always be the same as the working wavelength. Because optical fiber loss varies with light wavelength, you will get incorrect result if your measuring wavelength is different from the actual working wavelength. For example, if a system is designed for 1550nm but you test it with 1310nm light source and power meter, the result will not be correct.

2. The testing light source should be the same as the intended working lightwave equipment light source. If the system is designed for a LED source, you should test it with a LED source. If the system is designed for multimode laser light, you should use a multimode laser light source for testing. This is also true for single mode laser light source.

Fiber optic equipment used in a loss testing

In a basic loss testing setup, four types of test equipment are needed. They are the light source, the power meter, the reference patch cables and the adapter (mating sleeve).

Here are some considerations when choosing your equipment.

The light source should have the same wavelength as the operating equipment, proper mode (multimode or single mode, should be same as the operating equipment), type (LED or laser, same as the operating equipment) and proper connector.

The power meter should have the same wavelength as the light source, proper connector and calibrated.

The reference patch cables should be high quality with know loss, proper connectors and be the same type as the fiber plant being tested.

The adapter (mating sleeve) should be with high quality ceramic sleeves and be proper type (FC, SC, LC, etc).

Understanding dB (decibel) in fiber optic loss testing

As in any power measurement, fiber optic light power measurement unit can be expressed in milliwatt (mW), but a more convenient unit is dB(decibel).

Decibel (dB) is most often used in electronics testing. It is the ratio between two levels. One level is the input and the other level is the output. The ratio is calculated in logarithmic as explained below.

For power measurement, dB is defined as: dB = 10 x log(output power/input power)

So for example, after a fiber link, the output light power level becomes 50% of its input, the loss of the link will be 10log(0.5)= -3 dB.

Since dB is actually a ratio, it has no absolute units. So from above measurement sample, we have no idea of the actual power, may it be 0.1 mW or 1 mW.

That is why we have another unit dBm. It is the ratio of the measured power to 1mW of reference power. It is defined as: dBm = 10xlog(measured power/1mW)

So for example, a 0.1mW light power expressed in dBm will be 10xlog(0.1mW/1mW)=-10 dBm.

From above we know that dBm is a absolute unit, we know exactly how many mW it is.

For fiber optic loss testing, decibel is the most often used unit since it is much easier to work with. Why? Because two dB values can be simply added or subtracted. For example, a total fiber link may have three sections, each has loss of 0.5dB, 5dB and 0.5dB. The total loss can then be easily concluded as 0.5dB + 5dB + 0.5dB = 6 dB. You can try to convert it to actual milliwatt and you will see that I am right!

About the Author

Colin Yao is an expert on fiber optic communication technologies and products. Learn more about
innerduct coupler
,
innerduct for fiber
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plenum inner duct
on Fiber Optics For Sale Co. web site.