the device 20 contains a source of high frequency and high energy electromagnetic waves ( 10 - 100 mfz , 5 - 15 kw ). this electromagnetic energy is passed to two plates 10 with half cylindrical shape ( see fig3 ) that surround the infected palm tree stem 100 ( see fig1 ). device output power and exposure duration are adjusted in accordance with the stem diagonal , soil humidity and plates area . for longer stem diagonals , bigger plate area or high soil humidity , the device output power should be increased in order to destroy pests and achieve best results . the device 20 can be mounted on a transport car 30 . 1 . power supply source : main power source , which provides the required power for the device . for plantations or farms , it could be implemented through mobile ac or dc power generator . 2 . filtration and operation unit : through which device startup is achieved . it contains the means to isolate waves generated in the device , in order to prevent their reflection and interference with power supply source . 3 . control panel : through which various parameters are adjusted by the operator , such as exposure time , energy and delay time required to keep the operator within limits of safe distance ( several meters ). when exposure process starts and ends , proper sound alarming is used . 4 . high frequency oscillator : high frequency / low power generating circuits ( 10 - 100 mhz / parts of watt ). generated frequencies are determined by pest selectivity and allowed by government frequencies . universally allowed frequencies for scientific , industrial and medical uses are : 13 . 56 , 27 . 12 , 40 . 68 mhz . practically , i found that 40 . 68 mhz frequency is the most effective and have the best selectivity . 5 . power amplifier : waves at the output of the frequency generator are characterized with law energy . this building block amplifies the frequency power up to 5 - 15 kw . 6 . power level control unit : this block guarantees the frequency power stability , which may be affected by several factors such as in stability in source power or device units heat - up . 7 . monitoring and alerting unit : it continuously monitors the generated waves and compares them with required . in case of difference , the unit alarms and automatically stops the device ( for more safety ). 8 . output matching networks : it provides the compatibility between the output impedance of the power amplifier and the load impedance ( palm tree stem ). it &# 39 ; s based on the open wires balanced type matching networks . the device load ( palm tree stem ) is characterized with complicated combination of pests capacitance , inductance and resistance , and the output matching network unit is positioned near the stem and connected to the power amplifier through a proper long coaxial cable 11 . 9 . contact wires : metal conductors for transmission of electromagnetic high frequency waves . characterized with high conductivity and covered with high quality isolation material . they are lengthy enough to connect output matching network unit to stem surrounding plates . 10 . stem surrounding plates : two replicated half - cylindrical or flat well electrically isolated surfaces metal plates to surround the stem and upper roots of the infected palm tree ( fig3 ). an improved plate design 15 ( fig4 ) closes the upper area of the plates and reflects dissipated waves . it also provides good exposure of upper roots area through a widened round base . it covers one or more metal rod 16 ( grill type ) electrically isolated from the reflector ; that serve as an aerial for transmitting required waves which will be concentrated and reflected by the plates toward the stem and visible root for best effect . the design of surrounding plates can be made by one flexible insulated metal sheet , covering the full circumference of the stem , similar to the way that the cuff of a blood pressure tester covers a patient &# 39 ; s arm . this gives a better way of covering the stem , leading to the uniform distribution of energy at the infected area and minimizng the dissipated energy by using the tree roots as an ideal virtual discharge ground electrode . as known , the direction of the electromagnetic displacement current flows to the low potential zone ( ground ). this will oblige the use of a different type output matching network called “ unbalanced ” type . this way of improvement extends coverage area to reach deeper into the roots at the time of the treatment process . using electromagnetic high frequency waves to fight against destructive pests hiding inside tree stems using a mobile device is a new sure idea in such battle , which distinguishes it self from chemical insecticides and other materials 5 which may affect human life .
a high frequency power source and supplies electromagnetic waves that are supplied to a single or a pair of plates that surround a trunk of the infested tree . the electromagnetic waves are used to kill red palm weevils and trees stem borers within the trunk of the tree . the plates are cylindrical , half cylindrical or flat , with insulated metal sheets that surround the trunk and upper roots of the infected tree .