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Calculate the power out put of an amplifier that has an input of 15 μw and a gain of 25dB?
Wiki User
∙ 14y ago
If you want to work in watts, convert 25dB to a scalling factor:
3dB = 2 x input
10dB = 10 x input
20dB = 100 x input
...25dB = 10 ^ (25/10) = 316.2 x input
So the output is 15 micro Watts x 316.2 = (4700)/(10^6) = 4.7 milli watts
If you want to work in dB, then convert 15 micro watts to dB:
10 * log |P| = dB = 10*log |15 x 10^6| = -48.2dB
***When you have very small (ie negative) dB, it is often referred to in dBm, or 1/1000 of dB ( 30 dBm = 0 dB)
so the output is -18.2dBm + 25 = 6.8dBm, or -23.2dB
Wiki User
∙ 14y ago
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Calculate the power out put of an amplifier that has an input of 15wand a gain of 25dB?
If you want to work in watts, convert 25dB to a scalling factor: 3dB = 2 x input 10dB = 10 x input 20dB = 100 x input ...25dB = 10 ^ (25/10) = 316.2 x input So the output is 15 Watts x 316.2 = 4.7kW If you want to work in dB, then convert 15 watts to dB: 10 * log |P| = dB = 10*log |15| = 11.76dB so the output is 11.76 + 25 = 36.76dB
What is the maximum distance of QR860 cable that can be used with a 25dB gain amplifier QR860 has a cable loss 1.24dB100 at 750 MHz.?
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How do you hook two 25dB RF amplifiers together to provide amplification greater than 25dB for cable TV reception?
The amps can be "cascaded" i.e, connected in series, but only if the input capability of the second amp is higher than 25 db, which is doubtful. More than likely the second amp will cross-mod (distort) the signal broadband. Typical broadband RF amp maximium input levels are +15-20db. If you need high gain for a cable drop, the Blonder-Tongue ACA-30 amp or BIDA series amps offer output levels of around +48db with a +10-15 db input signal. They're your best bet.
What distance is the sound intensity level 25dB?
That depends on the sound intesity level at the point of origen. Sound fall of with the square of the distance but the original intensity must be known.
25dB equal to how many watts?
That depends on you. If you want, you can say 1 watt should be 0 dB.
What the strongest FM signal booster?
The effectiveness or strength of FM signal boosters is roughly measured in "db". Db means decibels, a measure of signal strength above noise. A quick search revealed boosters for sale ranging from 14db to 25db. More db = stronger.
What are difference between absorber and sound barrier?
Building materials with specific acoustic properties may be divided into Sound Barriers, and Sound Absorbers.Sound barriers are usually materials with significant mass and are used to stop sound between rooms. Concrete Bock and gypsum wallboard would be typical examples.It is very important that sound barrier installations are essentially airtight, otherwise the sound waves will bypass the barrier through tiny holes or slits.The performance of a sound Barrier is measured in decibels. Useful barriers will have a loss in the range of 25dB to 60dB. dB = decibel.The elasticity and mass of air are very different from those of concrete. When a sound wave passes from one medium to another, there will be reflection of energy when the elasticity and mass properties of the two mediums are different.Alexander G Bell was the first person to have to measure the energy loudness of sound. 1 Bell reduction (=10 deci bels) sounds like a reduction to 1/10. The scale is logarithmic, so 2 Bell (20 dB) = a reduction to1/100. Thus a reduction of 50 dB is equivalent to a reduction to1/100 000 of the original.Sound Absorbers are generally light weight material and frequently porous. They are designed to stop reflections within a room. The sound waves are absorbed by moving the light weight fibres within the material. The percentage of sound absorbence of a material would range from 30% to 95%. These values are very different from the values associated with a barrier material.The unit of sound absorbence is the Sabine and 1 (imperial) Sabine has the absorbence of 1sq ft of perfect absorber. Or 1 metric Sabine has the sound absorbence of 1 sq metre of perfect absorber.
Why FM is clearer than am?
The abbreviations FM and AM stands for amplitude modulation and frequency modulation. The reason why FM is more clearer than AM is because FM has a better signal-to-noise ratio than AM does.
What do they ask at midterm 2 Aries hardware?
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