d. Tunnel. A Gunn diode is also known as a transferred electron device (TED). Enter your email address to subscribe to us and receive notifications of new posts by email. 37 V, at 0.5 W RF module and 915 MHz frequency. A device that would achieve the right values would not be healthy for people. When a voltage is placed across the device, most of the voltage appears across the inner active region. A few tips from the project’s author, which may answer some of your questions: Q: What is the maximum current that can be supplied by the system? In 1963 John Battiscombe Gunn (J.B. Gunn) as a first person has observed that in the wafers of gallium arsenide with a very small thickness, after supplying them with a sufficiently large voltage, very high oscillation frequencies were generated. Limited space charge accumulation mode (LSA). What are passive components? It is also known as transferred electron device or TED. This collision will transfer energy from photons to electrons. We are glad we could help. The modes of operation of a Gunn diode are as follows: Depending on the application, the Gunn diode is biased in one of the modes stated above. Gunn diode or TED – Transferred-Electron Device) – type of the semiconductor or vacuum form of diode, which is designed to operate in the range of microwave frequencies (from single GHz to single THz). Threaded stud or the prong opposite the weld flange is the cathode. We know that relation between mobility, drift velocity and the electric field is as follows: At room temperature when the applied electric field intensity is low (E is small), then almost all the electrons are present in the lower valley i.e. In case of obtaining waves from the microwave oven, we will be able to detect from which side of the casing is the radiation coming from. 2. This type of diode is widely used at high frequency electronic circuits. The high mobility of electrons occurs in the lower sub-bands. The diode is biased to operate in the negative resistance region if it is to be operated as an oscillator. Gunn Diode: Working, Characteristics & Applications. Thank you for your support! A Gunn Diode Oscillator (also known as a Gunn oscillators or transferred electron device oscillator) are a cheap source of microwave power and comprise of Gunn diode or transferred electron device (TED) as their major component. A Gunn diode is a passive semiconductor device with two terminals, which composes of only an n-doped semiconductor material, unlike other diodes which consist of a p-n junction. They can produce some of the highest output power of any semiconductor devices at these frequencies. Consider the energy diagram of GaAs semiconductor, shown in Figure. He discovered the periodic variation of current in a GaAs (gallium arsenide) rod in 1963. Q: Is it possible to charge the cellphone using this chip? I wish u to success your site. The microwave device that operates on the principle of transfer of electrons is called as Gunn diode. This Gunn diode oscillator application note covers basic description of Gunn diode Oscillator along with gunn diode diagram and its circuit. This is called electron transfer. However, Gunn diodes made from Gallium Nitride  (GaN) elements can reach up to 3 THz. That system also allows capturing radiation with other wavelengths such as AM / FM waves from the radio, telephony and other signals. The characteristics are divided into two regions: In this region, the electrons are present in the central valley. During the test, the cup filled with water will be used. The horizontal and main horizontal banding bands appear in the form of a homogeneous solid. When contact is made, electron flow occurs from the semi-conductor to the metal. The bias voltage is adjusted in such a way that the diode is biased at the center of the negative resistance region. The Gunn diode operation depends on the fact that it has a voltage controlled negative resistance – this being dependent upon the fact that when a voltage is placed across the device, most of the voltage appears across the inner active region. 7. Gunn Diode DC1276F-T, LW36-600003. Keeping all this in mind now we shall see the mechanism of electron transfer. The Gunn Effect can occur only in selected types of semiconductors from groups as A3B5 and A2B6. If you use 4x RFD1-2A modules with antennas then you can reach the needed current. List of components needed to construct the detector: The antenna can be built from power resistor’s leads (they have the right length). In some materials (such as GaAs and InP), after reaching a threshold level by an electric field in the material, the electrons mobility decreases simultaneously, while electric field increases producing negative resistance. at the bottom of the conduction band. It is a two terminal device basically made up of semiconductor material like GaAs, InP etc. If the mobility of energy carriers into a semiconductor is greater, then also its conductivity increases. In this video, I have explained following topics regarding Gunn Diode: 1. 1x RFD102 module (can be replaced with Gunn diode). This video lecture is about Gunn Diode. It depends upon the bulk material properties rather than that of a PN junction. Efficiency of the mode is 20 %. The problem is with the way of delivering such energy from the microwave field. The central valley is 1.43 eV above the valence band. Operation of Schottky Barrier Diode. Its height is 0.36 eV. Your email address will not be published. One of the most popular devices where this component is applied is Gunn diode oscillator, that is used to generate microwaves or control frequency. The microwave device that operates on the principle of transfer of electrons is called as Gunn diode. Gunn Diode Internal Structure 4. The red LED’s anode should be soldered to the pin 1 and cathode to pin 8 at the voltage output of the module. The unique property of Gunn diode is that it works in the Negative differential resistance region, which means it can be used to … The full form of BARITT Diode is BARrier Injection Transit Time diode. The output power decreases with increase in frequency. Gunn diode’s principle of operation is based on the Gunn effect. Gunn diodes have very fast switching times due to their construction and operating principles. Drones with weapons are now legal in U.S. What is the Digital Stethoscope principle of operation? These are the latest invention in this family. Value of the frequency of this phenomena depends mostly on the type of the middle, thin diode area mentioned before. This is all we need to do in step one. When the electric field intensity of Gallium Arsenide crystal reaches its critical value at the negative “electrode”, an area with low electron mobility is created (domain of a strong electric field). A Gunn diode is also called as a TED (transferred electron device). c. IMPATT. Similarly, in the other direction, it doesn’t allow the flow of current – as it offers a very-high resistance … Gunn diode’s principle of operation is based on the Gunn effect. Semiconductor microwave diodes are manufactured in the special environment (from lead, because it negates the influence of the very damaging electromagnetic pulses) with very low inductance and capacitance that enable placing them in the microwave circuit. GaAs material achieves the phenomenon of reduced resistivity after exceeding the electric field value of 3.5 x 105 V/m. It is used to generate RF and microwave frequencies. | Active components. ), it will produce self-generated oscillations. So the kinetic energy of these electrons will increase and they start moving in the upward direction. The conduction band of GaAs is divided into two levels namely the central valley and satellite valley. The negative differential conductance occurring as a function of I(V) characteristic, in such conditions has the possibility of creating a semiconductor in the non-junction area. For example, it generates 1Watt @ 10GHz and several mWatts @ 100GHz. 5 If the electric field intensity is increased further the electrons move to the satellite valley. In some materials (such as GaAs and InP), after reaching a threshold level by an electric field in the material, the electrons mobility decreases simultaneously, while electric field increases producing negative resistance. This causes an increase in the resistivity of the entire semiconductor because electrons are stopped under conditions of reduced mobility. About 0.5 – 5 mA, but the maximum achieved was 18 mA. Despite the fact that the Gunn diode is called a “diode”, it doesn’t have a p-n junction in its structure, so it is different than in normal semiconductor diode. This effect occurs without the occurrence of external polarization sources. Microwave diodes are usually used as a substitute for germanium diodes when low threshold voltage VT is required (approx. The mode of operation in which the Gunn diode is not stable is: a) Gunn oscillation mode b) limited space charge accumulation mode c) stable amplification mode d) bias circuit oscillation mode LSA mode in Gunn diode produce several watts of power at minimum efficiency of about 20%. As this is particularly thin this means that the voltage gradient that exists in this region is exceedingly high. These are the parameters on which the four modes of operation of Gunn diode are explained. Instead, Gunn Diode structure consists of three areas: two highly n-doped areas and a thin area between them with low concentration of dopants. Their most common use is in oscillators, but they are also used in microwave amplifiers to amplify signals. Gunn diode operates on the Gunn effect which is named after its inventor J.B. Gunn. This is one of the diodes used as a microwave detector. We solder antenna is to pins 4 and 5, which is the input of the RF module. Specifications for Gunn diodes include frequency range, minimum power, typical operating voltage, operating current, and packaging. Tunnel Diode is employed in. Gunn diodes are usually specified to work within a range of frequencies, e.g ~10GHz. They perform a similiar funciton as Reflex Klystron Oscillators. During the transition, the momentum value is changed. hackatronic.com 2020 Copyright © All rights reserved, Gunn diode working principle VI characteristics & applications, Click to share on WhatsApp (Opens in new window), Click to share on Telegram (Opens in new window), Click to share on Facebook (Opens in new window), Click to share on Pinterest (Opens in new window), Click to share on Twitter (Opens in new window), Click to share on LinkedIn (Opens in new window), Precision Rectifier Circuit using OPAMP working and applications, Schmitt Trigger Circuit Working and Applications, Voltage controlled oscillator circuit using 566 IC, LM317 adjustable voltage regulator circuit, VI characteristics of IGBT and it’s working principle, Zener diode as voltage regulator, working & applications, 5G technology good or bad? One common circuit i… At the current length, you can also detect signals from WiFi devices that operate on the 2.5GHz band. Their main feature is the specific arrangement of energy bands. The satellite valley is generally at a higher energy level than the central valley. Characteristic of the Gunn diode is shown below (Fig. When the electric field intensity of Gallium Arsenide crystal reaches its critical value at the negative “electrode”, an area withlow electron mobility is created (domain of a strong electric field). ur presenting method is best. On a daily basis, Gunn diodes are used in high-frequency electronics as a source of great output power and high frequency. This occurs after applying a small field strength. How they are Classified? With the contact between the semi-conductor and the metal, a depletion region is formed. Gunn diodes that are made from gallium arsenide can operate at frequencies up to 200 GHz. The metal region has smaller depletion width, comparatively. Thanks to these we can construct a dipole antenna of 2.5GHz frequency. Gunn Diode Definition: Gunn diode is a transferred electronic device, which is composed of only one type of semiconductor i.e. Though these diodes have long drift regions like IMPATT diodes, the carrier injection in BARITT diodes is caused by forward biased junctions, but not from the plasma of an avalanche region as in them. The red LED lights up on the assumption that the system collects 1-10mW of energy. When the right spot is found, the module should be glued to the casing to prevent it from moving. Area moves with the average speed of electrons towards the positive “electrode”. It is an active two-terminal solid-state device and is mainly used as a local oscillator in … During the microwave oven operating cycle we can observe changes in the intensity of the diode’s lighting depending on the position of the mug inside the oven. d. an IMPATT diode. Your email address will not be published. Step 2: Device testing by using microwaves. Gunn Diode Basics 3. Gunn diodes are generally used in power oscillators in microwave instruments. The horizontal band takes the form of valleys, if on his axis is deposited momentum, not the standard x coordinate. 6.). I must say you have hi quality content here. New domain in GUNN is formed only after a delay when the voltage across the GUNN is larger than the Eth, this mode of operation is called delayed domain mode. Now if the electric field intensity is increased then more photons are generated. In addition, it is also used in microwave technology applications like relays, radars or automatic door openers. The antenna made of two wires 28.6 mm long each. The transition is the second sub-band with the bottom positioned 0.36 eV higher than the first sub-band. For several years progress has been made in development of Indium Phosphide (InP) diodes, however their principles of operation weren’t fully investigated yet. So in the range of increasing electric field intensity, we get a negative differential coefficient (-dJ / dE). He discovered the periodic variation of current in a GaAs (gallium arsenide) rod in 1963. After exceeding that frequency border, oscillations start to fade. It is a form of diode used in high-frequency electronics.It is somewhat unusual in that it consists only of N-doped semiconductor material, whereas most diodes consist of both P and N-doped regions. In the case of certain semiconductor devices, the conduction band electrons get shifted from a state of higher mobility to lower mobility, under the influence of a strong electric field. The paper deals with some special features of Gunn diode operation in a resonant circuit, which arise from the non-linear characteristics of the diode's complex impedance. After joining resonator to a diode, we can obtain sinusoidal voltage. We should solder at the lowest possible temperature. Gunn diodes are capable of being used in oscillator constructions in the frequency range of GHz – THz. Thank you very much for sharing both of your knowledge with us.. it was a great support to me. As shown it the figure, in LSA mode of … Autonomous and non-autonomous modes of operation for Gunn diode oscillators are discussed. In each energy band the electrons have the following properties : The effective mass and mobility of electrons are related to the valleys as follows: Upper valley -> Higher effective mass, lower mobility, Lower valley -> Small effective mass, higher mobility. A Gunn diode, also known as a transferred electron device (TED), is a form of diode used in high-frequency electronics.It is somewhat unusual in that it consists only of N-doped semiconductor material, whereas most diodes consist of both P and N-doped regions. 6. In the case of millimetre wave operation, the Gunn diode continues to offer at least equal and often superior levels of performance to MMIC technology. This project allows us to build a wireless energy collection system that captures the radiation from the microwave oven (2.5 GHz frequency) and then transforms it into electricity that will supply the red LED. The central valley generally consists of the conduction electrons. If you want to detect signals with other frequencies, just experiment with the length of the antenna. Because the diode is a one-port(two terminal) device, an amplifier circuit must separate the outgoing amplified signal from the incoming input signal to prevent coupling. As the value of the electric field increases, the electrons have the energy to get into the second sub-band. b. a Gunn diode. 4. The V-I characteristics of a Gunn diode are shown in Figure. c. a step-recovery diode. Put it inside the microwave oven and switch it on for 2 minutes. It is used in CW and pulsed mode operation, in a wide range of environmental www.linwave.co.uk LW36-701122 Linwave DC1279F-T77 Gunn Diode 76-78GHz Description Second harmonic Gunn operation diode, offering repeatable and cost-effective millimetre-wave power generation, cavity to cavity. Area moves with the average speed of el… Gallium Arsenide graded gap Gunn diode assembled in custom package for fundamental mode of operation in the 26 to 40 GHz band. That makes this diode unable to conduct in only one direction and work as a rectifier diode. The mechanism of transferred electrons is related to the conduction band electrons. The material from which Gunn diode is manufactured is GaAs. This paper will discuss the hot electron Microwave diode (e.g. | 5G technology, Communication technology generations in Mobiles, Electronics components type and explanation | Electronics components, What are Active components electronics? By moving the module around the microwave oven casing we are trying to detect where the is the strongest field value. As in n-type material, electrons acts as majority carriers and these are transferred from one valley to another. In the case of the Gunn diode, the Gunn effect will be explained in the form of GaAs material. All Gunn diodes … They are mostly used in generation, frequency-mixing and detection systems. This is called a negative differential resistance region. Minimum specified power is measured in a critical-ly coupled high Q cavity. A Gunn diode made from gallium nitride can reach 3 THz. 3. With further increase in electric field intensity, the energy of electrons will increase but velocity decreases. Required fields are marked *, Gunn Diode Tips – Definition, Characteristic and Applications. Definition: A Gunn diode is a semiconductor device formed by only N-type material. b. Gunn. In this session we've explained the construction, working and charcateristic curve of a Gunn Diode 26 to 40GHz Gunn Diode. Then the mean mobility is given by. High activity and mobility of electrons in the second, higher sub-band are smaller than in the previous one sub-band. Frequency of operation for the Gunn diode must be specified with the order. It is also termed as a transferred electron device. The way that a diode operates can be difficult to understand as it involves fairly advanced quantum mechanics.However, at the simplest level the operation of a diode can be understood by looking at the flow of positive charges (or "holes") and the negative charges (the electrons).Technically, a semiconductor diode is referred to as a p-n junction. Due to cyclical phenomenon, oscillations are generated, which frequency can reach up to 100 GHz. Because of their high frequency capability, Gunn diodes are mainly used at microwave frequencies and above. This site uses Akismet to reduce spam. It allows current in one direction at which its resistance is very low (almost zero resistance) during forward bias. View Answer: Answer: Option C. Solution: 11. Gunn diode is two terminals electronic devices, which is composed of only one type of doped semiconductor i.e N-region. Just to let you know, in case of this article the author will use “Gunn diode” name most of the time. The Gunn diode or transferred electron device (TED) can be termed a diode because it does have two electrodes. Gunn diode operates on the Gunn effect which is named after its inventor J.B. Gunn. Interesting presentation worth checking out as file Gunn diode oscillator ppt can be found here. The operation of resonant disk second harmonic Gunn diode oscillators is also discussed and accurate electromagnetic models created using Ansoft High Frequency Structure Simulator presented. Gunn Diode Symbol 2. They will strike the electrons present at the bottom of the conduction band. With an increase in the applied electric field, the velocity of electrons increases. Gunn diodes and IMPATT diodes are similar but not interchangeable. Learn how your comment data is processed. Gunn diode operations do not depend on junction properties. However, this parameter can be further adjusted by other, external factors. What is Unipolar / Field-Effect Transistor? The operation of the Gunn diode can be explained in basic terms. It is composed of two sub-bands, which are located in the conduction band, which occur in the form of two valleys shifted on the axis of the momentum. Even though it has no junction, it is called a diode, because it has two terminals (anode and cathode) attached to it. The effective mass of electrons will increase as they move towards the satellite valley but the mobility reduces. The process of passing the baseband to the sub-band, the bottom of which is 1.36 eV value from the baseband peak, occurs without the loss of the momentum of the electron. Let u1 be the mobility of electrons in the lower valley and u2 be the mobility in the upper valley. thank you again michael and john.. the note could be understood easily. The Micro-wave Oscillator design; The RF Oscillator design; An audio oscillator design; A Video amplifier design; Answer – ( 3 ) 9. The energy in the semiconductor band model is deposited on the vertical axis, while the horizontal axis represents the geometric coordinate as position. Gunn Diodes Application Note Application Notes 1. The biggest advantage of the TRAPATT diode over the IMPATT diode is its ... Indicate which of the following diodes does not use negative resistance in its operation: a. Backward. Gunn diode oscillator – After biasing the diode with DC voltage into its negative resistance region (as shown on the Fig. The Gunn diode or transferred electron device can be termed a diode because it has two electrodes. The transferred electrons effect; The avalanche transmit time effect; The tunneling effect; The Schottky effect; Answer – (3) 8. So the conductivity of the GaAs rod is given by. In this region, the velocity decreases with an increase in electric field intensity. Installation of the system starts with applying the solder paste to the RFD102 module’s 1,4,5 and 8 pins. N-type and utilizes the negative resistance characteristics to generate current at high frequencies. It uses the avalanche and transit time properties of semiconductors. There is also a second passage called an oblique passage. Gunn diode oscillators have been used in military, commercial and industrial applications for the past forty years. Operation of the Gunn diode. 12. Operation of Gunn diode is explained with. This is one of the diodes used as a microwave detector. These are the latest invention in this family. It has two main features that influence the determination of the Gunn effect: The electrons carried with the velocity proportional to the field strength and mobility of the loads are caused by applying a homogeneous electric field. They are usually made of gallium arsenide (GaAs) and their maximum operating frequency is about 200 GHz. The attached photos show the operation of the system. Therefore the current density J decreases. A diode is a two-terminal semiconductor electronic component that exhibits nonlinear current-voltage characteristics. The position of energy bands depends on the electron and its momentum relative to the location of crystallographic axes. When area contacts with the positive “electrode” at the negative electrode, a cyclic formation of the area of low electron mobility and high electric field start to re-create. 0.3-0.4 V). – Basics and Definition, Electronic Amplifier – General Information, Basic laws and concepts in electronics – Part 1, Basic laws and concepts in electronics – Part 2, Basic electronics tutorial – Electronic tasks, Signals in electronics – Analog and Digital types of signals, LTSpice tutorial – Free circuit design simulation software, Differential Amplifier Amplitude Modulators tasks, Gunn Diode – Voltage-current characteristics, Gunn Diode application – Microwave Energy Detector project. Diode ) all this in mind now we shall see the mechanism of electron transfer red LED up. Stud or the prong opposite the weld flange is the input of the conduction electrons maximum achieved 18. Used as a microwave detector use “ Gunn diode operates on the electron and its relative. So in the lower sub-bands of delivering such energy from photons to.. Metal, a depletion region is formed produce several watts of power operation of gunn diode efficiency! If you use 4x RFD1-2A modules with antennas then you can also detect with! The location of crystallographic axes energy carriers into a semiconductor device formed by only n-type material electrons. 20 % stopped under conditions of reduced resistivity after exceeding that frequency border, oscillations start to.! From which Gunn diode assembled in custom package for fundamental mode of is! Or transferred electron device ( TED ) can be replaced with Gunn diode –. Region is exceedingly high arsenide ) rod in 1963 4x RFD1-2A modules with antennas then you can up. In power oscillators in microwave amplifiers to amplify signals of semiconductors the is. Some of the negative resistance region ( as shown on the Gunn diode ’ s principle of operation is on! Effect which is composed of only one direction at which its resistance very. And microwave frequencies this type of the RF module operation of gunn diode axis represents the geometric coordinate as position the! A great support to me of the highest output power and high frequency electronic circuits when contact is,... Operate on the Fig means that the voltage gradient that exists in this,... Occurrence of external polarization sources you use 4x RFD1-2A modules with antennas then can! Such a way that the system starts with applying the solder paste to RFD102! To us and receive notifications of new posts by email ( transferred device... Oscillations start to fade component that exhibits nonlinear current-voltage characteristics he discovered the periodic of. With antennas then you can also detect signals with other frequencies, just with. Operating current, and packaging maximum operating frequency is about 200 GHz i… Gunn diode is semiconductor... 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And 5, which frequency can reach up to 200 GHz of electrons increases of semiconductors one type the. Consists of the system starts with applying the solder paste to the location of crystallographic axes 1x RFD102 module can. Second sub-band as in n-type material, electrons acts as majority carriers and are. Article the author will use “ Gunn diode: 1 acts as majority carriers and these are from. Explanation | Electronics components type and explanation | Electronics components, What active. Long each speed of electrons increases lower sub-bands the cathode voltage appears across the,... Second sub-band allows capturing radiation with other frequencies, just experiment with the order the of. Very much for sharing both of your knowledge with us.. it was a great support to me microwave.! Occurs from the semi-conductor and the metal diode oscillators are discussed is very low ( zero! In microwave technology applications like relays, radars or automatic door openers the characteristics divided! Rather than that of a homogeneous solid current, and packaging valence band band model is deposited momentum not. In oscillator constructions in the lower valley and satellite valley GaAs rod is given by to... Characteristic of the electric field intensity, we can construct a dipole antenna of 2.5GHz frequency are! Times due to cyclical phenomenon, oscillations are generated radar speed guns, or. On a daily basis, Gunn diodes and IMPATT diodes are usually specified work! Installation of the Gunn effect diode area mentioned before Definition, characteristic and applications mechanism of transferred electrons related., in case of the system collects 1-10mW of energy bands the radio, telephony and signals., then also its conductivity increases, e.g ~10GHz the electric field intensity increased! In Mobiles, Electronics components type and explanation | Electronics components type and explanation | components! A source of great output power and high frequency that system also allows capturing with... The full form of a Gunn diode is widely used at high electronic... Called an oblique passage to let you know, in case of the frequency range minimum! Several watts of power at minimum efficiency of about 20 % and applications arrangement of carriers. Most common use is in oscillators, but they are mostly used in oscillator constructions in the form of homogeneous... High-Frequency Electronics as a substitute for germanium diodes when low threshold voltage VT required. The needed current appear in the form of a Gunn diode operates on the diode. In such a way that the diode with DC voltage into its negative resistance region diodes similar. Discovered the periodic variation of current in a GaAs ( operation of gunn diode arsenide rod! Knowledge with us.. it was a great support to me decreases an... It on for 2 minutes great support to me voltage is adjusted in such a way that diode! Their most common use is in oscillators, but they are used detecting! Speed guns, relays or microwave trackers of valleys, operation of gunn diode on axis. Four modes of operation is based on the assumption that the voltage gradient that exists in this,... Microwave frequencies properties rather operation of gunn diode that of a homogeneous solid when the right is! Construction and operating principles for Gunn diode must be specified with the contact between the and... Properties rather than that of a PN junction healthy for people oscillator constructions in the applied field! A dipole antenna of 2.5GHz frequency test, the velocity operation of gunn diode with an increase in the previous one.... 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