An arbitrarily shaped microstrip patch antennaDesign a quarter-wavelength microstrip impedance transformer to match a patch antenna of 80 Ω with a 50-Ω line. The microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance (Zo) and electrical length or vice versa. Always perform a Solve Ports Only solution to ensure the waveport is correct. 06/27/2007: EM Talk Blog added. The microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance (Zo). 27 mm at 5. Press Synthesize to see the results. Model Setup. They are suitable for vehicle based satellite link antennas, global positioning systems, radar for missiles and mobile handheld radios. The substrate parameters (ε r and h) and the frequency of interest are required. Hello, It's difficult to do what you called 'simulation of microstrip line using MATLAB', but if you just want to have a width and length value, for certain impedance and electrical length at certain frequency, you could get it from transmission line calculator from Microwave Office or ADS. The substrate parameters (ε r and h) and the frequency of interest are required. “Microstrip Patch Array Antenna with Inset Fed and Perturbation for a 3 GHz S-Band Coastal Radar. The four element antenna array has demonstrated about 16dbi gain, a remarkable figure for its compact size. 1. Microstrip vs. The microstrip line will be designed on a substrate with a dielectric constant of 10. Patch antenna online calculator. 1. 1 Trophy points 1,298 Activity points 2,319 Hi all I am not able to understand the meaning of input impedance (edge) in this link em: talk - Microstrip Patch Antenna. Abstract and Figures. The proposed antenna is designed using the artificial neural networks (ANN) method based on the multilayer perceptron structure; it is composed of a coplanar. Patch antennas usually have narrow bandwidths and the 5-GHz WLAN band extends from 5. Units do not matter; use same units for (w) and (h), waveport size will be in the same units as (w) and (h). Figure 1. files/HFSS/MPA. 1 Ohm (by calculator on EMtalk and not very correct patch autognd port in sonnet lite). 8 W/Kg has been demonstrated that outperforms than the exiting imaging methods [ 10 ]. There is no such optimal value (Radiation resistance determines the power that is radiated by the antenna,Higher the better) and you can do feed point for the patch using the equation presented in the balanis book or send me over your microstrip patch design,i will do it for you. Second possibility: Search „microstrip patch antenna calculator“ with Google and you get this link to an online calculator, which isMicrostrip Impedance Calculator. 2 mils then, Z d = 96. 4 for 0. 8% was observed. The basic model of a microstrip transmission line is shown in Fig. ZO. most intuitively appealing models for a microstrip antenna. ” Journal of Electromagnetic Analysis and Applications. They hadlarge in intensity and extravagant because of the province. A low profile, unidirectional, dual layer, and narrow bandwidth microstrip patch antenna is designed to resonate at 2. This parameter is used for the loss calculations. At low frequencies near 0 GHz, the input impedance is inductive since. 711. The substrate parameters (εr and h) and the frequency of interest are required. 5 GHz and calculate its resonant frequency. Hits: 6158. Calculates dimensions of circular microstrip patch antenna, provided frequency, relative permittivity and height of substrate. Search first posts only. The calculator is set up to handle an asymmetric arrangement, where traces are not centrally located in the PCB layer stack. the calculator for microstrip line in emtalk asks for "elctrical length in degrees" and i am not able to calculate. To use this tool, enter the values for. R w = Terminating resistance between two. 05/25/2007: Printed Dipole Antenna using Ansoft Designer added in the Tutorials\Tools section. Circuits are printed as shown in the following figure. So. In addition, if GAMMA, VSWR, or dB is known, the calculator can convert between the three. 25 GHz dielectic const = 2. Yes, the inset is discussed in Balanis. 3. The microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance (Zo) and electrical length or vice versa. 12LNO/0. Regards. hfss em: talk - HFSS Tutorial 3:. This is an approximation, it doesn't include G12, or the correction to G1 to account for the patch width. To determine the width (W), the microstrip patch antenna calculator was used to provide an initial starting point. Disadvantages include: Limited bandwidth (usually 1 to 5%, but much more is possible with increased complexity. Wu Odd and Even mode fields in microstrip have different percentages of total field fringing through air which changes effective Er Leads to velocity variations between even and odd +1 +1 +1 . everything RF has created a series of RF calculators to help engineers and students with common calculations that they need to conduct frequently. The antenna array with dimensions of (9 × 40 × 0. 4 and 5 GHz. 6. The unit vector, n, is normal to the patch edge. Two antenna miniaturization techniques, based on the use of a Koch fractal contour and a shorting post (connecting the patch to the ground plane), are combined to enable a major size reduction. The microstrip patch antenna array was designed to achieve a higher gain and bandwidth compared to a single element antenna. Discover (and save!) your own Pins on PinterestA new technique is presented for designing microstrip patch antennas with very good input impedance matching. A rectangular microstrip patch antenna is proposed. The relation between the R, Zo, and amount of power division is given by the following formula. . The microstrip patch antenna calculator determines the length (L) and width (W) of a rectangular microstrip patch antenna for a given resonant frequency or vice versa. title="Microstrip. Because of small size, light weight, less cost and good performance these types of antennas are also used in spacecraft, satellite and missile applications []. The substrate parameters (ε r and h) and the frequency of interest are required. The microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance (Zo) and electrical length or vice versa. Microstrip Patch Antenna Calculator Formula. em: talk - Company Info. 5 mm thick substrate with εr = 4. The microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance (Zo) and electrical length or vice versa. Placing an inset for a microstrip feedline into the antenna. But I get stuck at port = FDTD. In this paper, a review of the existing theory of chara. 4 GHz (24002483. Enter values for W and L for a microstrip line to determine its Zo and Electrical Length. to NF. Intrinsic techniques, proximity coupled and aperture-coupled patches, applying horizontally coupled patches to driven patch on a single layer and stacked patches are discussed. For example, if you wish to input "25000000", just type "25M" instead. Microstrip line calculator. The patch is of length L, width W, and sitting on top of a substrate (some dielectric circuit board). 7. This calculator is designed to calculate the inductance of a microstrip given its dimensions (width, length and the distance of. It is an Excel Calculator for a Microstrip Rectangular Patch Antenna. 0 GHz; the width of the microstrip is designed for 50 Ω and the length for a 180 degree phase delay. The antenna is fed by a microstrip line with 50 Ω characteristic impedance and. 28, tangent loss of 0. Model Setup. The microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance (Zo). If you include these you might get 144 ohms, I don't know what they are claiming to calculate. See full list on emtalk. Unequal-split Power Divider Calculator. The range for antenna is chosen between 2. To use the calculator, place values in either the velocity of propagation field or the dielectric constant field. This calculator is designed to calculate the inductance of a microstrip given its dimensions (width, length and the distance of. 8e9); rfplot (spar)Coax connector placement location for patch antenna connection. The dimensions of the patch is 4. The four element antenna array has demonstrated about 16dbi gain, a remarkable figure for its compact size. The substrate has a dielectric constant εr. Using the microstrip line calculator, a width of 1. 4. P B = Power output of Port 3. A simple tool to calculate parameters for an edge fed/inset fed/probe fed patch antenna or microstrip antenna. A low profile, unidirectional, dual layer, and narrow bandwidth microstrip patch antenna is designed to resonate at 2. The proposed 1 × 8 arrays. This antenna does not take any much extra size and can be etched on the same mobile PCB itself. Patch. Your results will be the height and width. Pennsylvania State University. The input impedance, Zin, of the shorted microstrip line is shown in Figure 3. On the other hand, the type of conductive material used, and. The coaxial cable, along with the balanced two-wire, is the most common type of transmission line used in RF communications. Take the square root of (W+Dh) x (H+Dh), then divide that subtotal by two. The design process started with the conventional rectangular microstrip patch antenna as shown in Figures 1a and 1b. Microstrip Crosstalk Calculator Stripline Crosstalk Calculator. Equation (14-20a) states. The patch antenna calculator link. The patch. 3 Design Specification simulated an inset-fed rectangular microstrip patch antenna for WLAN Before designing a microstrip patch antenna, the first step is to application using CST software and a RO4350 dialectic substrate, consider the design specification of the antenna based on. Antenna are designed with a working frequency of 3,5 GHz for 5G and 5 GHz communication systems for. Analyze. Both can be realized in microstrip, stripline or even coax, but stripline is the go-to technology for coupled-line couplers. High Integrate Broad-Band Microstrip Antenna Array Using Multilayer Printed Circuit Board (MPCB) Technology. This parameter is used for the loss calculations. 0 GHz. 09/08/2007: Online VSWR calculator added. 12 mm, a height of 1. Coaxial Cable Impedance Calculator. 45 GHz. In the present work an attempt has been made to design and simulation of rectangular microstrip double patch antenna for X band using microstrip feed line techniques. Hi, i'm designing some microstrip antennas and i have some questions. The designed antenna is realized using microstrip line feed on a 1. A miniaturized antenna with low power levels of 3. The feed lines are made of similar length so the beam pointing is broadside to the array at all frequencies. 214. Microstrip Calculator With thanks to David Campbell for the use of this calculator Substrate Parameters εr: Relative permittivity of the substrate. The passive antenna is a critical part of any wireless communications link, for both transmit and. Figure 1. This paper refers to a detailed analysis on the design and implementation of 4×1 and 8×1 microstrip patch antenna (array) of given specifications using IE3D software and a dielectric material FR4 with dielectric substrate permittivity of 4. Finally, there is a bandwidth that can be defined in the frequency domain (units of Hz). Figure 1. com i found that for the 100ohm line the width calculated is so low, 0. The dielectric substrate material used for this purpose was FR4 with 1. This design approach helps analyzer microstrip inset-fed patch antennas and helps to locate the exact inset length for 50-? input impedance. The input impedance at the radiation edge is also. Synthesize Enter values for Zo and Electrical Length to determine the physical width and length of the microstrip line. This is a commonly used transmission line, as it can be cheaply fabricated using printed circuit board techniques. Z 0 = Single Ended Impedance. The substrate has a dielectric constant εr. 946 for silver, or 1. Analyze Enter values for W and L for a microstrip line to determine its Zo and Electrical Length. Press Analyze to see the results. 45 GHz on a flexible substrate material. Feeding is extremely important with the patch antenna, and it contributes to bandwidth, crosspolarization levels, and ripple. The patch antenna, shown in Figure 11. t is the Thickness of track (1 oz/ft2 = 0. The microstrip coupling lines provide the input/output coupling and its strength are determined by the gap width and length (S 2, L 2 and S 3, L 8). The microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance. em: talk - HFSS Tutorial 1: Microstrip Patch Antenna See there are a lot many books from where you can get those formulas to calculate the length and width of the patch antenna. The microstrip patch were evaluated and designed using approximate equations in Balanis [5] to get the dimension of the ground plane. Formula for Differential Microstrip Impedance Calculator (Using Zo) Where, Z d = Differential Impedance. Microstrip patch antennas (MPAs) are rapidly gaining more attention due to the proliferation of communication devices and systems with frequencies becoming more suitable for the size and performance of this type of. Initially, some common mediums of communication such as WIFI/WLAN and Bluetooth were targeted. 27 dB and bandwidth of 150 MHz with a gain of 7. Note: Units do not matter for this calculation as long as they are consistent. Pasternack's Microstrip Patch Antenna Calculator determines the length and width (in millimeters) of a rectangular patch antenna. 5 GHz and 17 GHz within C and Ku bands, respectively. I measured patch dimensions of two X-band microstrip sensor antennas on 1. With our handy calculator, you can choose from 50 Ohm, 75 Ohm, 93 Ohm and 95 Ohm coaxial cables. Model a microstrip patch antenna using two feed methods (pin feed, microstrip edge feed). Circular microstrip antennas are used as low-profile antennas in airborne and spacecraft applications. Coplanar Waveguide Calculator. . This paper presents a social spider optimization (SSO) design of a small-size microstrip antenna. Index Terms-Microstrip patch antenna, MATLAB calculator, CST, 2. Microstrip impedance calculator. In the case of the substrate, its dimensions are 5. Learn how to design microstrip and CPW power dividers using Keysight EEsof EDA tools in this technical overview. This can be set to zero, but the calculated loss will not include conductor losses. Below is the standard input impedance of an inset fed patch antenna at 2. Most RF Coaxial Cables have an impedance of 50 ohms or 75 ohms. For an embedded (internal) microstrip, the formulas provided in paragraph 4. The microstrip. Microstrip Line. 85 THz. At high frequencies, the effect of substrate permittivity on antenna performance is dramatically higher than low frequency microstrip antennas. Height: Height of the substrate. This design approach helps analyzer microstrip inset-fed patch antennas and helps to locate the exact inset length for 50-? input impedance. Calculation assumes that you are using a 50 Ohm microstrip transmission line. A microstrip width calculator can calculate the width of a microstrip. Left-handed materials have lead to novel microwave antennas, resonators, waveguides, and lenses. com Microstrip Patch Antenna HFSSv10 ( download simulation file) The microstrip patch antenna is a popular printed resonant antenna for narrow-band microwave wireless links that require semi-hemispherical coverage. 525 GHz. An embedded microstrip is a microstrip transmission line or flat conductor separated from the ground place via a dielectric material. RF calculations and conversions include metric-standard, link. 6-mm-thick substrate (ε r = 2. Units do not matter; use same units for (w) and (h), waveport size will be in the same units as (w) and (h). 04 in the ε eff formula for the W/H<1 case. 8e9,Z0=75); figure; show (mline); Plot the S-parameters of this line. It also provides examples and references for further reading. Yes, the inset is discussed in Balanis. emtalk, electromagnetics forum, electromagnetic tutorials, microwave engineering forum, microwave engineering tutorials, microstrip calculator Check Open neighbouring websites listThe microstrip calculator determines the width and length of a microstrip line for a given characteristic impedance (Zo) and electrical length or vice versa. The substrate parameters (ε r and h) are required. Additional benefits of patch antennas is that they are easily. An individual microstrip antenna consists of a patch of metal foil of various shapes (a patch antenna) on the surface of a PCB (printed circuit board), with a metal foil ground plane on the other side of the board. The amplitude increases as the coupling length increases up to a point. There are two types of cross talk forward and backward crosstalk. The. This link is listed in our web site directory since Saturday Jul 11 2015, and till today "Patch Antenna Calculator" has been followed for a total of 1156 times. Introduction In recent years, the microstrip patch antenna has widely been used for various specific applications in satellite communications, aerospace, radars, biomedical applications, mobile communication for GSM, and remote sensing applications [1] because of its special features like ease of analysis and fabrication, low cost, light. 508 mm How to Design 2. 2. 45/5-GHz WLAN bands. 3mm (100Ohm). em: talk - HFSS Tutorial 1: Microstrip Patch Antenna A patch antenna is a miniature, surface-mountable antenna. For suspended plate-type patch, to find exactly where is this point I cut narrow slot in the patch, install connector from the bottom of Ground plane and slide the patch along the connector to find this sweet spot. 45 GHz Microstrip Patch Antenna Using CST The patch antenna calculator link It’s cable. Height: Height of the substrate. py. 2 Length of the patch, in µm. 0. a a = Physical Radius of Patch. It could also be used to control multiple patch arrays. 2 thickness = 0. 4. The characteristic impedance (Z o) of coplanar waveguide with ground or microstrip lines with signal side ground plane can be calculated using the active calculator or the equations at the bottom of the page. In simple case i thought we have three impedances: patch edge, matching line, 50 ohm line. The calculation of the length of the first dipole was carried out based on the lower operating frequency than 1. com - Anthony. Microstrip-fed patches have very narrow bandwidths, almost invariably less than 5%. Press Analyze to see the results. We used the emtalk website [5] to determine the length and width of the antenna patch, where we used FR-4 as the dielectric (dielectric constant = 4. Other parameters for circular patch Design Other parameters for designing the hexagonal shape are reactance of circular patch and resonance frequency. Enter values for W and L for a microstrip line to determine its Zo and Electrical Length. files/HFSS/PPWG_DD. HFSS is one of the better solution for Patch antenna design. Crosstalk occurs when a signal "jumps" from one trace to another, a phenomenon that is unintentional and often unwanted. RF and Wireless tutorials. A new technique is presented for designing microstrip patch antennas with very good input impedance matching. em: talk - Electromagnetics and Microwave Engineering. This calculator helps you determine the magnitude of the crosstalk that could occur on a microstrip given its dimensions and source voltage. em: talk - HFSS Tutorial 1: Microstrip Patch Antenna. Efficient. Benefits of Microstrip Patch Antenna Transmission situated operations. By default, the dimensions are chosen for an resonant frequency of 15 GHz. Different studies have been published in this area for the amelioration of the patch antenna. Its feeding mechanism is accomplished through inclined aperture slots in the ground plane. A single element, 1×2 and 2×2 microstrip rectangular patch antennas were designed and simulated in Computer Simulation Tool (CST) Microwave Studio. 3), 0. 002 and height of 1. 27 mm 3 and the substrate material is Rogers RT/duroid 6010/6010LM. In order to design and simulate this array of two by one with microstrip line feed technique, the software used was the Computer Simulation Tool (CST) by Microwave. com in 2 categories. An arbitrarily shaped microstrip patch antennaType of antenna: Rectangular Microstrip Patch antenna Resonance frequency: 2. patch and reduce the length by this amount you will find a final length of 13. 5 Microstrip Line. A patch antenna is a miniature, surface-mountable antenna. In the work of Ab Wahab et al. Patch antennas usually have narrow bandwidths and the 5-GHz WLAN band extends from 5. em: talk - Company Info. A microstrip is a type of transmission line in which a strip of a conducting material like copper is mounted on a dielectric material and routed to a ground plane. Rho: Conductor resistivity relative to copper. I have designed a antenna at 2. 4 GHz which is applicable to. Microstrip Impedance Calculator & other calculatorsThe wider is the crossection of the patch the closer this point is to the edge of the patch. Following equations or formula are used for this microstrip patch antenna calculator. 15 to 5. 1: Geometry of inset-fed microstrip patch antenna Table 1: Physical dimensions of inset-fed microstrip patch antenna Operating frequency, in GHz 10 Dielectric constant, ε 2. em: talk - Legal Statement; em: talk - Tutorials. 8e9,Z0=75); figure; show (mline); Plot the S-parameters of this line. The microstrip line will be designed on a substrate with a dielectric constant of 10. 5e9,ForAI=true) pAI = AIAntenna with properties: Antenna Info AntennaType: 'patchMicrostripInsetfed' InitialDesignFrequency: 4. If you only need to convert between GAMMA, VSWR, and dB, you can ignore Zo and ZL. Our RF calculators and converters will provide the figures you need for your radio frequency engineering needs. This calculator is designed to calculate the characteristic impedance of a microstrip - a flat conductor suspended over a ground plane with a dielectric between them (see diagram below). 8 GHz and with a characteristic impedance of 75 ohms. When you want to determine the width and length of a microstrip line for any given characteristic impedance and electrical length, or vice versa, a microstrip calculator is the right tool to do so. spar = sparameters (mline,1. 6023 Ω. First, i'm using an inset-fed retangular patch ready for 50ohm and i need to match it to a 100ohm microstrip line. A simple tool to calculate parameters for an edge fed/inset fed/probe fed patch antenna or microstrip antenna. 8 GHz, which makes the design challenging. While commonly constructed using printed circuit boards, this structure can also be built using other materials as long as there is a conductor separated from. To use this tool, enter the values for. This calculator is designed to calculate the characteristic impedance of an edge-coupled microstrip. Always perform a Solve Ports Only solution to ensure the waveport is correct. Such a microstrip is constructed with two traces referenced to the same reference plane with a dielectric material between them. This constant dielectric changes with temperature. pAI = design (patchMicrostripInsetfed,4. Be aware that there are many microstrip impedance calculators on the Internet that give sometimes widely varying results. Les meilleurs smartphones "pas chers" à moins de 200 euros de mai 2023 - CNET FranceDesign Microstrip Transmission Line Around 1. The plots show the magnitude and phase of the input impedance. This tool will also give you the magnitude of the coupled voltage between. 8), the ratio of W/H for fifty-ohm microstrip is about 95%. But here is the funny part. The substrate parameters (ε r and h) and the frequency of interest are required. When a Teflon dielectric substrate is used, the resonant frequency is 12. Use the patchMicrostripTriangular object to create a triangular microstrip patch antenna. The model of the printed dipole is shown in Fig. Track Thickness: mm. 27 mm at 5. Enter values for L and W for the microstrip patch to determine its fr. The 40 data samples are used to design MSA from which details of 15 data samples have been given in table 1. 70x 38. 8x4. The substrate parameters (ε r and h) and the frequency of interest are required. hfss em: talk - HFSS Tutorial 2: Dispersion Diagram I files/HFSS/PPWG_DD. This paper explains about a 3x3 Rectangular microstrip patch antenna Arrays using HFSS 14. 4. However, I tried to simulate the exact shape of the antenna (the design from the paper) and developed the project on HFSS initially. An X-band, 12-element array of rectangular microstrip patches was demonstrated for the first time to reflect the main beam 20 degrees off broadside. 42 GHz and 3. **Note: Like our stripline impedance calculator, all of our RF calculators allow SI prefix input. Description. 45 * λ 20, 0. In this case, each coordinate in the vector starts at the origin and lies along the specified points on the x-, y-, and z-axes. I would like to design microstrip patch antenna. For example: F=10. Adopted from A CPW-fed Rectangular Patch Antenna for WLAN/WiMAX ApplicationsIn HFSS you can do this by de-embedding (there is a tutorial on emtalk. Before you get started with the "Microstrip Patch Antenna Array" course, watch the recorded video of a live webinar showing from antenna element design to an antenna array design to platform analysis from element to space - all in one workflow. Enter values for W and L for a microstrip line to determine its Zo and Electrical Length. If you have questions, comments, and/or suggestions please contact me by email: support "at" emtalk. You can start with simpler formula: L ≈ 0. The voltage standing wave ratio (VSWR) calculator determines reflection coefficient (GAMMA), VSWR, and return loss (dB) for a mismatched line. 2,578. 29mm, on the 0. 1. . Circular microstrip antennas are used as low-profile antennas in airborne and spacecraft applications. Cons-•Narrow bandwidth •Low efficiency •Low Gain Figure 1 –Microstrip Antenna [1] 1. 825 GHz. This work suggests a new form of dual-band patch antenna for radio frequency identification applications (RFID) in the UHF band and the microwave band. A microstrip transmit patch antenna with harmonics suppression property has been designed for the 2. Three-dimensional far-field radiation pattern of a microstrip patch antenna (2. This calculator is designed to calculate the characteristic impedance of a microstrip - a flat conductor suspended over a ground plane with a dielectric between them (see diagram below). . The patch antenna developed for 436MHz by Greg (VK3BLG) in 2003 is a remarkable antenna for amateur satellite work. Wheeler and was published in, "Transmission-line properties of a. It has a global. The substrate parameters (ε r and h) and the frequency of interest are required. 35%. The microstrip patch antenna calculator determines the length (L) and width (W) of a rectangular microstrip patch antenna for a given resonant frequency or vice versa. Increasing the width of the patch reduces the radiation resistance and increases the bandwidth. Hi, i'm designing some microstrip antennas and i have some questions. 4. This example shows how to create an AI model based inset-fed microstrip patch antenna at 4. A 50 Ohm microstrip transmission line is matched to a patch antenna (impedance typically 200 Ohms or more) via a quarter-wavelength microstrip transmission line with the characteristic impedance chosen to match the load. If the dielectric constant of the material is not known, you can choose to put in the velocity of. Two points in space, specified as a 2-by-3 matrix corresponding to two three-element vectors of Cartesian. py. 09/08/2007: Online VSWR calculator added. f r f r = Frequency. 0x1. Pasternack's RF Calculators and Conversions section provides engineers valuable and easy-to-use tools ranging from complex mathematical formulas to simple conversions. 2 permittivity substrate is studied. 2. The edge couple differential microstrip transmission line is a common technique for routing differential traces. Enter values for W and L for a microstrip line to determine its Zo and Electrical Length. A 60 GHz high-gain four-element series-fed microstrip patch array antenna is presented. 24 Ω Feeding method: Microstrip Line Feed The design procedure of rectangular microstrip patch antenna is as follows The Length and Width of the microstrip patch antenna is calculated by the Microstrip Patch Calculator,A microstrip is created by etching a trace on a printed circuit board and is mostly used in microwave applications. 42 GHz and 3. A microstrip width calculator can calculate the width of a microstrip. 0x1. Site Map . Here's a microstrip patch antenna calculator from Jonny: After downloading numerous MSExcel Spreadsheet calculators from MW101, I thought I might contribute one.