water impurities , such as calcium , magnesium , iron , and other chemical compounds , form a scale which , over time , adheres to the interior walls of water pipes . in water heaters and steam boilers the scale formation occurs even faster , which leads to the increase in energy consumption , downtime of facilities , and premature equipment wear and tear . water treatment using an electromagnetic field prevents the scale formation due to the fact that microcrystals of calcium carbonate ( forming deposition ) are transformed into a needle shaped crystal lattice ( aragonite ), resulting in less adhesion to the inner surfaces of pipelines and other used equipment . some of such devices are able to transfer an electric charge of opposite polarities into the water solution to affect the suspended solids . the attraction of oppositely charged particles launches the processes of flocculation and coagulation ( enlargement of suspended solids ). this reduces the consumption of chemical reagents ( flocculates and coagulates ) and improves the functionality of filter systems . it is possible to improve the treatment of water solutions with an electromagnetic field including more precise and selective impact on the treated objects and modifiable program of the device depending on the content of a treated fluid . all material objects consist of atoms and molecules that are oscillating . the smallest particles vibrate with the highest frequency and the oscillation frequency decreases with increased mass and complexity of objects . a resonance phenomenon occurs when the frequency of external oscillations matches the resonant frequency of the object . it is expressed through the multifold increase of the oscillation amplitude . research in this field shows that the precision of matching to a resonant frequency is more important than the power of the external oscillation . accurate frequency selection creates a great resonant effect even with an extremely low power of the electromagnetic field , even with 1 - 10 μw / cm 2 . therefore , the efficiency of water solution treatment is significantly improved by the accurate selection of the frequency of an electromagnetic field matching with resonant frequencies and the subharmonics of those resonant frequencies corresponding to chemical compounds and ions from the fluid ( in contrast with random frequency selection as used in prior art ). examples of chemical compounds and ions that are involved in the creation of cluster structures include , but are not limited to , ca 2 +, ca ( oh ) 2 , caco 3 , caso 4 , mg 2 +, mg ( oh ) 2 , mgco 3 , fe 2 +, fe 3 +, fe ( oh ) 2 , fe ( oh ) 3 , and atomic hydrogen ( h +). most of the resonant frequencies for these chemical compounds are in the ehf ( extremely high frequency ) range . however , transmitting energy in the ghz range is quite challenging . the present invention propose the use of subharmonics to achieve an effect similar to that which maybe attained by using resonant ghz - range radiation . the subharmonic frequency , f , is a fraction of a resonant frequency , f , with the following relationship : f = f /( 2n ), where n = positive integer numbers . thus , the present invention affects chemical compounds and ions located in water with subharmonics in the radiowave range of 5 - 40 khz ( corresponding to resonant frequencies in the ghz range ). in preferred embodiments of the present invention , several subharmonics are used at the same time ( multiple impact , i . e . “ accord ”) or , alternatively , sequentially . this invention is based on the “ spe - effect ”; the affect with any resonant frequency of a water molecule is exciting the molecule on the fundamental resonant frequency of 1 ghz . secondly , it is based on the fact that the spe - effect exists in water solutions of inorganic compounds , including those which are insoluble in water . additionally , the change of the water solution content with the addition of insoluble compounds shifts the fundamental resonant frequency of mixture as a whole in a unique way . the fundamental resonant frequencies of chemical compounds may be defined and determined by various known methods , for example : ( 1 ) from open sources ; ( 2 ) calculation based on geometry , spatial models , and physical properties of a compound ; ( 3 ) using methods from bio - medicine and their equipment , such as trans - resonant functional ( trf ) topographs . the principle of the trf topograph is to affect the tested solution with ehf ( extremely high frequency ) emission in a particular range with a small step . a radio response of the solution is recorded . high amplitude response corresponds to the resonant frequency of the solution . the following is an example approach for water treatment using the invention : the investigated resonance frequency ( ghz ) is divided by 2 several times until the frequency becomes radio frequency . let us call this frequency as n - th harmonics . then , by dividing by 2 again , we obtain m - th harmonics , and then by dividing by 2 once again , we obtain l - th harmonics . the water solution is treated according to the program for the investigated chemical compound and the results are analyzed . the following is an example of how the present invention may be used for a quick assessment a water solution : the treated water solution is boiled for 1 hour and then cooled down . a visual analysis of formed micro crystals should be performed using a microscope . an additional step employing a trf topograph may also be performed . the program employed by a device according to the present invention may further comprise frequencies responsible for the inhibition of bacteria or protozoa . the treatment of bacteria and protozoa requires a multiple processing of the water solution . a quick assessment of the bacteria and protozoa treatment may be performed with a bacterial luminescence test - kit such as “ ecolum .” the final program may have a set of precisely defined subharmonics , and one or several narrow frequency sub - ranges , where frequencies are formed randomly or pseudo - randomly with a deviation of 1 - 2 % from precisely defined subharmonics . this technique is especially useful because of potential seasonal changes in the content of a water solution . sometimes , the program may shift higher or lower from the given frequency in a very small range in small steps , using the fuzzy logic principle . in addition , the program and / or sub - ranges of resonant frequencies maybe corrected to correspond to the water solution content of a specific geographical region , a temporal ( seasonal ) change , or other specific variations . the programmable microcontroller running the program according to one embodiment of the present invention supports at least 20 mops ( million operations per second ) in order to modulate pulses with a frequency of a certain accuracy and a simple set of resonant frequencies . more complex programs require a more powerful microcontroller with support for 40 mops and higher . in addition , the transfer of the electromagnetic field into a fluid is transmitted through a magnetic core comprising ferrite with a high magnetic permeability . the ferrite core is positioned externally around the pipe or other object . this is the most effective way to transfer the energy into the solution with minimal losses . the magnetic core is preferably detachable and sectional , for convenience . the combination of small amplitude pulses and a primary pulse is more efficient for the treatment of water solutions with an electromagnetic field , likely due to the background excitement of the fluid . accordingly , the present invention comprises a device comprising a typical generator according to a resonant amplifier scheme . generated frequencies are induced through a ferrite core and into a pipe with a fluid , the generated frequencies comprising pulses which are sinusoidal with exponentially decaying amplitudes . the first pulses with maximum amplitude are given the maximum energy and the decaying pulses provide the background excitement to the treated fluid . the number of cycles in the pulse may be , e . g ., from 7 to 15 . the fundamental frequency of the resonant amplifier in this example is 130 - 190 khz . the device further comprises an indicator , reflecting the peak amplitude of the induced signal . this is very useful as a diagnostic of proper device functionality and setup accuracy . both are valuable for customers and / or customer service . the device or method disclosed herein may further comprise a fluid reaction tank , an absorbent filter , a fluid pump , an air compressor , an air valve , fluid valves , a drain channel and control elements . two or more synchronized devices according to the present invention may be installed for water solution treatment through one or more magnetic cores around a large diameter pipeline . additional devices may be necessary to compensate the electromagnetic field attenuation in the magnetic core . fig1 represents an example device for treating a fluid , implementing the method according to the present invention . a digital display 5 , showing the peak amplitude of the induced electromagnetic field , is placed on top of the device 1 . the housing 1 of the device is exteriorly attached to the pipe 6 by means of detachable ferrite core sections 2 and a primary ferrite core section 4 , which extends through the device housing land exits on the opposite side . the connection of ferrite sections 2 by brackets 3 is further shown in fig2 . as indicated above , the device is a hardware - software complex . it maybe configured to affect the chemical compounds in water solutions with an alternative electromagnetic field . the frequencies of the electromagnetic field correspond to the subharmonics of fundamental resonant frequencies of compounds located within a fluid . fig2 shows an enlarged image of the connection of detachable ferrite core sections 2 , by using hinges 7 and spring brackets 3 . fig3 shows an example circuit diagram implementing the method according to the present invention . the device is controlled by a powerful microcontroller 15 , which allows the execution of the embedded programs for water solution treatment corresponding to specific content in particular geographical regions or the specific source of the fluid . the programmable microcontroller 15 modulates rectangular pulses with variable frequencies according to the embedded program , using a pulse modulator 16 . the duration of the pulse is constant and approximately 3 μs . the pulse modulator 16 opens the transistor 13 of the resonant amplifier through a driver ( buffer ) 14 . when the transistor 13 is opened , the electric current travels through the exciting generator winding 8 , the winding 8 being placed around a primary section 4 ( see fig1 and 2 ) of the ferrite core 10 . thus , an electromagnetic field is induced in the ferrite core 10 ( comprising a primary section 4 and multiple detachable sections 2 , thus surrounding a pipe or other object ). this creates oscillations in the resonant contour : inductor 9 - capacitor 11 . the resonant contour forms sinusoidal pulses . at this moment , the capacitor 12 discharges and transfers additional energy to the resonant contour and increases the intensity of the initial pulse . when the transistor 13 is closed , the external power to the resonant contour energy is cut off , and oscillations in the contour slowly decay . continuing with fig3 , the device further comprises a monitoring circuit that monitors the amplitude of the alternative voltage . the signal emitted from a control winding 18 , which is coupled to the ferrite core 10 is transmitted to an operational amplifier 19 , then to a filter and peak detector 20 , and then to the microcontroller 15 . once within the microcontroller 15 , the monitoring circuit signal is digitized by an adc ( analog - digital converter ) 17 , further analyzed ( comparing the obtained amplitude with a predetermined threshold ) by the control unit 22 and transferred to the display controller 21 , and finally transmitted to the digital display 5 , thus allowing the indicator to reflect the oscillation amplitude in digital form . a comparator 23 is also included for catching signals which may cause an error , which are labeled as such before being transmitted to the display controller 21 and digital display 5 . fig4 shows an example block diagram of a water treatment facility employing the method of the present invention . the method comprises a device according to the present invention 100 , positioned along a pipe 6 between the input stream of fluid 22 and the fluid reaction tank 24 . the method further comprises an absorbent filter 29 with quartz sand or similar , a fluid pump 25 providing multiple circulation of water , an air compressor 26 , an air valve 27 , fluid valves 23 and 28 , a drain channel 30 , an output ( i . e . treated ) stream of fluid 31 , and control elements . the fluid pump 25 provides a multiple circulation of the treated water solution through the device 100 . when the fluid has an excessive amount of dissolved iron ( fe 2 + ), the air compressor 26 injects oxygen ( from the air ) into the bottom part of the fluid reaction tank 24 . the air is necessary for intensive oxidizing of iron ions . the excessive air is removed from the fluid reaction tank 24 through the air valve 27 . the treatment of water solutions by the device 100 promotes the coagulation and flocculation of suspended solids and the intensive oxidizing of iron ions . iron oxides and suspended solids are easily filtered with the absorbent filter 29 . the absorbent filter based on quartz sand ( or the like ) improves the efficiency of coagulation due to the contact coagulation effect . the absorbent filter 29 should be cleaned periodically using the drain channel 30 . fig5 shows a graph of the waveform of a voltage induced in the ferrite core 10 . initial pulses 32 with maximum intensity corresponding to the subharmonics of resonant frequencies are the major impact on the treated fluid . time m corresponds to the m - th subharmonic , time n corresponds to the n - th subharmonic and time l corresponds to the l - th subharmonic . decaying pulses are marked as 33 . thus , initial pulses 32 may form an “ accord ” together with the next sequence of pulses . the present invention provides for a significantly improved cleaning and treatment efficiency in comparison with analogs , due to the precise and selective impact on compounds via use of subharmonic frequencies and combinations thereof . the program creating the sequence of pulses is also very flexible and is not random , thus also improving upon the prior art . the program further allows for the ability to implement several approaches for pulse sequences . finally , the digital indicator additionally provides a way to check the efficiency of the treatment and further acts as a useful troubleshooting tool . the description of a preferred embodiment of the invention has been presented for purposes of illustration and description . it is not intended to be exhaustive or to limit the invention to the precise forms disclosed . obviously , many modifications and variations will be apparent to practitioners skilled in this art . it is intended that the scope of the invention be defined by the following claims and their equivalents . moreover , the words “ example ” or “ exemplary ” are used herein to mean serving as an example , instance , or illustration . any aspect or design described herein as “ exemplary ” is not necessarily to be construed as preferred or advantageous over other aspects or designs . rather , use of the words “ example ” or “ exemplary ” is intended to present concepts in a concrete fashion . as used in this application , the term “ or ” is intended to mean an inclusive “ or ” rather than an exclusive “ or ”. that is , unless specified otherwise , or clear from context , “ x employs a or b ” is intended to mean any of the natural inclusive permutations . that is , if x employs a ; x employs b ; or x employs both a and b , then “ x employs a or b ” is satisfied under any of the foregoing instances . in addition , the articles “ a ” and “ an ” as used in this application and the appended claims should generally be construed to mean “ one or more ” unless specified otherwise or clear from context to be directed to a singular form .