Andy's Tool Box recent changes. Ver 3.5l * Added Polar coordinates to real and imaginary numbers. Useful when some datasheets express impedance and Mag and Phase angle. Ver 3.5j * Added how to determine a source impedance. Ver 3.5h * Transformer impedance ratio calculator had text transposed between primary and secondary input fields. Corrected. Ver 3.5c * Added RF Power probe measurements. Ver 3.5b * Added some URL's Ver 3.5a * Minor cosmetic changes * Some URL changes * Attenuation through concrete added Ver 3.3b * Added barometric pressure conversion. Ver 3.3 * Taken some common Amidon core data which was pictorial and converted to text. The Amidon data is NOT meant to be a complete listing, just a very simple guide. It also makes the whole spreadsheet size 50% smaller ! * Galactic noise now shows normalised figures for SSB and CW. * Added Maidenhead calculator. Enter 2 grid squares and it returns distance and beam headings. NOTE: May not work on all spreadsheet packages - your mileage may vary ! Tested OK on MS Office 2003,Nokia 9300 series PDA Phone, Lotus 1-2-3 Millenium edition. Maidenhead calculator is not available for MS Excel version 4. * URL updates (many update/new url's) * Added more cell comments. Ver 3.0 * Revamped Amidon data. * Added new page showing Amidon pictures and examples of nomenclature. [Not Excel V4 !] * Fixed Excel 2003 missing AF filter. Ver 2.0 * New help system. Cell comments now feature all formula and explanitory notes. These auto pop up with MS Excel and form a useful reference without having to open up the readme.txt etc. * Amidon data improved * Update URL's, plenty of component references, datasheets. * Added RC AF filter design Ver 1.3 * A couple of cells had no formula in them. Probably caused by an incompatable copy and paste action - Fixed. * FM bandwidth calculation now shows modulating index as well. * Added formula to determine unknown impedance of feeder. * Added formula to convert milliwatts to dbm * Added formula to convert dbuV to dbm (assumes 50 ohm terminal EMF). * More useful URL's * More data points added for E/F layer hop vs distance. * Chart now shows distances in both miles and kilometres. * Small addition to feeder losses section * A small correction in this help file. * Some additional notes added to this help file. * More help notes when the cursor is placed over a cell. * A wire guage conversion chart is shown in the skin effect section. You can view a SWG vs AWG chart when placing the mouse cursor over the cell. Ver 1.2 * Ohms wheel graphic added * E and F layer angle vs distance enhancements * Yet more URL's * Minor changes to help file notes (this file). Ver 1.1 * Added loop antenna impedance calculation * Attempt to make formatting more universal (cosmetic) * Added more useful URL's. Now includes over 80 useful URL's including packet radio,beacons,law,component suppliers (radio/tv), propagation,rig mods (6),useful radio sites etc etc! * Includes URL,email, phone and fax numbers * URL for http://www.furneauxriddall.com was incorrect. It should have been "LL" on the end. If using a spreadsheet program that allows clickable link embedding in a worksheet then these links will open your browser.NOTE: None of the PDA software I've seen so far allows this command. Usual Office type software WILL. [LIST OF AVAILABLE CALCULATIONS UPDATED September 2007] Loss though concrete Barometric pressure conversions Maidenhead distance and beam heading calculator Audio filters (RC networks) Unknown feeder impedance calculator Loop antenna impedance calculator FM bandwidth (Carson's rule) now includes modulation index. L network matching component values Capacitive and inductive reactances Bandwidth tuned circuit Radio range and VHF/UHF/Microwave Freespace path loss Resonance series tuned circuit Resonance // tuned circuit Power received from tx to rx Groundwave range calculation Near field (REACTIVE) region of an antenna Calculation of skin effect on conductors (2 methods) Series Resistance calculator for LED's, Lamps and crude nicad charging Impedance calculator including phase and power factor and relative SWR. Quarter wave transformer calculator Electrical quarter wave calculator Impedance of custom air spaced coax Air spaced capacitor designer All of Ohms law and power laws Conversion of AC and DC values RMS etc Conversion of milliwatts to dbm Conversion of dbuV to dbm Amidon cores inductance designer and related info included. Power and voltage decibel ratio's. Coax losses and approx capacity per 30cm Coax voltage breakdown and capacity per foot Single layer air cored inductance designer Capacitor markings guide SPARK GAP DISTANCES Resonant speaker tubes to act as CW peak filters db versus multiplication factor both power and voltage Galactic noise levels uV to dbm convertor Milliwatts to dbm convertor FONTS AND DISPLAY. If something doesn't look right you MUST ensure you are using the correct fonts on your machine - it's up to you to experiment. NOTE: Graphics may not work correctly on all PDA devices ! Pop up cell notes are dependant upon user software. The files in this package are: * ATB33b_office_2003.XLS * And the other .xls files are for Excel 4 versions! Just about all PDA's or software should be able to read Excel 4 version spreadsheets. USEAGE ------ Most features are self explanitory however some notes about useage are useful. IMPEDANCE OF UNKNOWN COAX IMPEDANCE ----------------------------------- You must use *1m* lengths for the input figures. Use an RF impedance bridge, measure impedances as stated for 1m lengths. LOOP ANTENNA IMPEDANCE ---------------------- Simply enter the loop antenna's area. E.g a 2.5 metre quad loop is 2.5m squared = 6.25m and the wavelength in use. If using a circular loop then remember that the area of a loop is 2*PI*radius! ANTENNA TUNER CALCULATOR ------------------------ <-------)))))))-------> | LO Z --- Hi Z --- | <---------------------> GROUND WAVE RANGE ----------------- This calculation is not an absolute figure and should be treated as a rule of thumb. Range depends entirely upon ground conductivity across the path, which obviously varies a great deal. Some of the path may be over seawater,some over land which varies by large amounts! NEAR FIELD REGION: ----------------- Near field region of an antenna is the region in which any conductive or lossy materials are placed will effect the antenna's radiation pattern. A quad loop will be the length on one of the sides - if it's a delta loop then whatever the longest side dimension is. Usually the same for an equalateral triangle. But a dipole will be the total length e.g. a 14Mhz dipole will be 10 metres. The formula used is - 2*Lż (squared) ---- lambda Where L = largest dimension of the antenna Lambda = wavelength. FM BANDWIDTH: ------------ Carson's rule dictates that the bandwidth of an FM signal is: Bandwidth = (2 x Highest modulating freq) + (2 x deviation). A modulation is index of 1 means that the bandwidth of the transmission is equal to the modulating frequency. A low modulation index means the bandwidth is less than the modulation frequency. SKIN EFFECT: ----------- This will show you the cut off frequency of the conductor before resistive losses start to increase. Losses increase the higher the frequency. The degree to which frequency affects the effective resistance of a solid wire conductor is impacted by the gauge of that wire. As a rule, large-gauge wires exhibit a more pronounced skin effect (change in resistance from DC) than small-gauge wires at any given frequency. Please remember that this figure is not impedance, and it does not consider any reactive effects, inductive or capacitive. This is simply an estimated figure of pure resistance for the conductor (that opposition to the AC flow of electrons which does dissipate power in the form of heat), corrected for skin effect. Reactance, and the combined effects of reactance and resistance (impedance), are entirely different matters. The formula expect the K factor to be derived from SWG. I have included an SWG <> AWG conversion table as both a pop up in the spreadsheet as well as in this document. Standard vs American Wire Gauge SWG Diam (in.) Nearest AWG 12 0.104 10 14 0.08 12 16 0.064 14 18 0.048 16 20 0.036 19 22 0.028 21 24 0.022 23 26 0.018 25 28 0.0148 27 30 0.0124 28 32 0.0108 29 34 0.0092 31 36 0.0076 32 38 0.006 34 40 0.0048 36 42 0.004 38 44 0.0032 40 46 0.0024 -- Guage size k factor ====================== 4/0 ---------- 124.5 2/0 ---------- 99.0 1/0 ---------- 88.0 2 ------------ 69.8 4 ------------ 55.5 6 ------------ 47.9 8 ------------ 34.8 10 ----------- 27.6 14 ----------- 17.6 18 ----------- 10.9 22 ----------- 6.86 QUARTER WAVE TRANSFORMERS: The circuit to visualise the effect of a quarter wave transformer is: | | ___________________| _____ =============___________________ (Where the _____ represents the inserted line. | | | Remember that the 1/4 wave means an ELECTRICAL quarter wave which depends upon the velocity factor of the transmission line you are using to construct the "transforming line". ANTENNA EFFICIENCY: ------------------ Earth resistance is the resistance that couples between the earth of the antenna and the earth of the soil. Example: Total resistance A<> B <> C) | | A | , ================== , | , | C , | , , , , , , , , , ,B --------------------------------------------------- /////////////////////////////////////////////////// SPARK GAPS: ---------- Peter G6KUI provided the following info - "Paschen's Law" Further searching brought up this empirical formula FOR AIR x=293 * p * d / (760 * T) [I refer to this as "Delta X" in my calculation] vbreakdown= 24.22 * x + 6.08 * sqrt( x ) where d= distance in cm. T= temperature in degrees Kelvin p= pressure in Torr ( mm Hg ) V in kV I have attempted to simplify the calculation which now assumes normal atmospheric pressure which is circa 1000mb and used centigrade instead of Kelvin. Subsequent investigation by myself reveals that Paschen's formula is used in relation to an infinate planar plate and it is *my* understanding so far that as such this formula can be applied to the traditionally held view of a plate capacitor of any size. Balls or pointed electrodes are a different matter. This formula may be useful for designing high voltage capacitors for ATU's etc. QUARTER WAVE SPEAKER CABINETS ----------------------------- Good for making and boosting particular frequencies in particular CW speakers! Just place the tube of desired dimensions over the loud speaker. _________________________________ _ /| |LS | TUBE \|_________________________________ 122.4 Ÿo Hz = ---------- (Tube length in metres)+(0.3*tube diameter in metres) AUDIO FILTERS ------------- This formula works for all of these configurations: 6db per decade. E.g. Cut off = 100Hz = -6db@1000Hz voltage | | >-----| |------------> | | | R R = High pass R >---------------|------> >----RRR-------------> | ------ = Low pass ------ | >--------------------> The cut off frequency is determined by the following formula: 1 ------------------- 6.283*R*C C= FARADS R= OHMS GALACTIC NOISE LEVELS --------------------- Formula used is: Power -dbW = 52-(23LOG10*FREQ MHZ)-204 Original from the ICEPAC technical Manual but note that there is an error in this manual - it says 52+23 which is incorrect (thanks VK2ZRG). BAROMETRIC CONVERSIONS ---------------------- To convert millibars to inches the formula is: Inches = millibars --------- 30.86 To convert inches to millibars: Millibars = inches*33.86 RF POWER PROBE: --------------- BAS70 +_____________|\|________________ | |/| | | - | | | | | | | |50R --- VOLTMETER | | --- 0.1u | - | | | | | ______________________|__________| Leads to voltmeter may need filtering. Power = ((Voltage measured + voltage drop of diode)) Squared ____________________________________________________________ 100R AC THEORY AND OHMS LAW: ----------------------- The following may be of use for reference purposes (thanks John !) when using Ohms Law in an AC environment. Ensure you choose suitable fonts in order to display correctly. The use of EDIT.COM is recommended. By G8MNY (New Nov 04) RMS is the DC equivalent power of AC, & for a sine wave is 70.7% of the peak value. eg the peak value is ū2 (1.414) time bigger than the RMS meter reading! Unlike DC circuits in AC circuits the power is the mean of the Instantaneous Power which is made from the instantaneous Voltage * Current. For complex non resistive power loads it is usual to use a term Power Factor to describe the rating factor to be applied to the RMS Volts * RMS Amps to get the true power rating. Some items are rated in Watts & some in VA depending on which is the safer limit for that item. At power stations the amount of Volt Amp Reactive (VARS) is monitored as a indication of how much wasted energy flows to & from the customers, just heating up the cables. ____ ===== ___ ===== ÄÄÄ“____ĆÄÄÄ ÄÄÄÄ“ĆÄÄÄÄ ÄÄÄ())))ÄÄÄÄ ÄÄ“___ĆÄÄ())))ÄÄ V Pure Resistive Pure Capacitor Pure Inductor Complex ³ _ _ _ _ ³ / \ ³ / \ ³ / \ ³ / \ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ “³ - - - ³ - - - ³ “³ - - - ³ - - - ³ “³ - - - ³ - - - ³ “³ - - - ³ - - - ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ \ _ / -³ \ _ / ³ \ _ / ³ \ _ / I IN PHASE LEADING LAGGING AT SOME ANGLE ³ _ _ _ _ _ ³ / \ ³ \ / ³ / \ ³ / \ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ ³ “³ - - - ³ - - - ³ “ - -³ - - - ³ Å - -³ - - - ³ - - Å ³ - - - ³ - - - ³ ³ ³ ³ ³ ³ ³ ³ ³ ³³ ³ ³ ³ \ _ / ³ \ _ / ³_ / \ _ ³ \ _ / POWER ³ _ _ ³ + & - Power ³ - & + Power ³ - & + Power ³ / \ / \ +³ Zero Net power +³ Zero Net Power +³ _ _ ³ ³ ³ ³ ³ ³ _ _ ³ _ _ ³ / \ / \ ³ ³ ³ ³ ³ ³ / \ / \ ³ / \ / \ ³ ³ ³ ³ ³ ³_/_ _ _\_/_ _ _\_ ³³ _ ³ _ ³ _ ³ _ ³ _ ³ _ ³ _ ³ _ ³ ³ ³ _ ³ _ ³ _ ³ _ ³ Power Sine Wave ³ ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³/ \_/ \_/ ³ @ 2x Frequency ³ \_/ \_/ ³ \_/ \_/ ³ some net power ³ -³ -³ -³ Power Factor 1.0 Power Factor 0.0 Power Factor 0.0 Power Factor 0.7 PHASE I Current <-, /³\ Current ŚÄÄÄÄÄÄÄ>V Lagging Rotation \ ³ Leading ³90ų Current -=ÄÄÄÄÄÄÄÄÄ>V | ³90ų ³ Lagging '-._ ķ Angle o ÄÄÄÄÄÄÄ>V & I ĄÄÄÄÄÄÄÄÄ>V \³/ '->I I Determine a source impedance. Simply place a resistance across the source (in parallel) and use the formula of - (Unloaded voltage - loaded voltage) - 1 multiplied by the resistance of the load.