Re: 800 watts how is this possible?
The wattage listed is peak-to-peak wattage, not all the time. Divide most P-t-P wattage ratings by 8 to get the true RMS power. (Root-mean-square, RMS power is an engineering measurement means for equating the total energy in an alternating current waveform to the average or heating power in a direct current circuit.) The rms power rating is 100 watts, indicating that pulses are being transmitted only about 1% of the time. The 800 watt peak-to-peak power rating is accounted for by the extremely short duration of each pulse. The rms power of most recreational depth sounders and fish finders range between 100 and about 600 watts. My X91, a top of the line finder just about 3 years ago is rated at 3,000 watts. Keep in mind- it's sending out a signal at 200Khz- we hear it as a "click". The human ear can only hear frequencies up to 20khz. In fact, if you your hand in the water near a transducer that is working, you almost "feel" the pulse more than hear it. A cheap finder now that costs under $100 will be an 800 watt unit, almost the lowest you can buy anymore. <br /><br /> Sound travels about 4 1/2 times faster in water than in air so that sound generated is moving fast. It also is transmitted better underwater with less sound loss. <br /><br /> I was puzzled at first too until I did some reading. It's amazing. <br /><br />UFM82
. The continuous power consumption is a fraction of the rated "power" of the tranducer, because the duration of the transmission is so small. In general, you can look at the recommended fuse for how much current the device can use worst case. Multiply that by 12v and you get wattage. <br /><br />Amir
