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Climate Change is Making Trees Grow Faster
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Climate Change is Making Trees Grow Faster

The change although welcome in the short-term could threaten the entire ecosystem in the long run.May 12, 2019When it comes to climate change, there is not much good news. From natural disasters to mass extinction, its effects are more than worrisome.RELATED: 7 OF THE OLDEST TREES IN THE WORLDThere is one area where it might be having a positive effect and that is tree growth.

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Vacuum Tube Sockets: Valve Bases

Vacuum Tube / Thermionic Valves Includes:BasicsHow does a tube workVacuum tube electrodesDiode valve / tubeTriodeTetrodeBeam TetrodePentodeEquivalentsPin connectionsNumbering systemsValve sockets / basesOver the years there have been very many different bases or sockets used for thermionic valves / vacuum tubes.
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Precision Connectors: PC 3.5 mm, PC 2.92 mm, etc

The Precision Connectors series of RF interconnections provides a very high quality series of interconnects for use where high precision is required.Often these RF connectors are used measurement applications, or where exceedingly high performance is required.The precision series of interconnections is typically intended for very high frequency RF, i.
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Quartz Crystal Ageing: long term stability & accuracy

Quartz Crystals, Xtals Tutorial Includes:Quartz crystals: xtalsWhat is quartzHow a crystal worksCrystal overtone operationQuartz crystal frequency pullingQuartz crystal cutsQuartz ageingCrystal resonator manufactureHow to specify a quartz crystalVCXOTCXOOCXOCrystal filterMonolithic crystal filterCeramic resonator & filterCeramic filter specificationsQuartz crystal resonators are used in filters and oscillators as high performance resonant circuits.
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Radio Link Budget: details & formula

Radio Propagation Tutorial Includes:Radio propagation basicsRadio signal path lossFree space propagation & path lossLink budgetRadio wave reflectionRadio wave refractionRadio wave diffractionMultipath propagationMultipath fadingRayleigh fadingThe atmosphere & radio propagationWhen designing a complete, i.
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Understanding Thyristor SCR Specifications & Parameters

Triac, Diac, SCR Tutorial Includes:Thyristor basicsThyristor device structureThyristor operationGate turn off thyristor, GTOThyristor specificationsWhat is a triacTriac specificationsDiac overviewWhen choosing a thyristor or SCR, there are several datasheet parameters that need to be understood so that the correct device can be selected.
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SMB Connector

The SMB connector is used in applications where a quick mating sub-miniature RF connector is required for RF frequencies up to frequencies of a few GHz.The SMB connector derives its name as it is termed a Sub-Miniature version B connector. It was developed as a result of the need for a connector that was able to connect and disconnect swiftly.
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HF Radio Propagation and Sunspots

Solar effects on propagation includes:Solar effects on radio propagationSunspotsSolar disturbancesSID sudden ionospheric disturbanceAs electromagnetic waves, and in this case, radio signals travel, they interact with objects and the media in which they travel. As they do this the radio signals can be reflected, refracted or diffracted.
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Antenna Feed Impedance

Antenna Basic Theory Tutorial Includes:Basic antenna theoryPolarisationResonance & bandwidthGain & directivityFeed impedanceA radio antenna is like any other form of RF load or signal source. It has a load or source impedance.In order to obtain the optimum performance the antenna feeder must be matched to antenna to ensure the maximum power transfer.
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Five Eighths Wavelength Vertical Antenna

Vertical antennas include:Types of vertical antennaQuarter wavelength vertical5λ/8 verticalAlthough the quarter wavelength vertical antenna provides a good level of performance, it is easy obtain some additional gain by extending the radiating element of the vertical antenna to five eighths of a wavelength, 5λ/8.
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What is Return Loss

VSWR & Transmission Line Theory Tutorial Includes:What is VSWR?Reflection CoefficientVSWR formulas & calculationsHow to measure VSWRHow to use a VSWR meterSimple SWR bridge circuitWhat is return lossVSWR / Return Loss TableReturn loss is a quantity often used within RF circuits where impedance matching is important.
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How to Buy the Best Antenna Tuner

Antenna Tuner Includes:Antenna tuner basicsHow to buy the best antenna tunerThere is a vast selection of antenna tuners or antenna tuning units, ATUs available on the ham radio market to purchase.Presented with the selection available, it is not always easy to know which one to select and whether all the options the more expensive ones offer will actually be used and be worth while.
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How to Measure VSWR: approaches & test instruments

VSWR & Transmission Line Theory Tutorial Includes:What is VSWR?Reflection CoefficientVSWR formulas & calculationsHow to measure VSWRHow to use a VSWR meterSimple SWR bridge circuitWhat is return lossVSWR / Return Loss TableAs VSWR is a key parameter that is particularly important for applications where transmitters are used.
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Parallel Resistor Values Table

Resistance Tutorial Includes:What is resistanceOhms LawResistivityResistivity table for common materialsResistance temperature coefficientElectrical conductivitySeries & parallel resistorsParallel resistors tableParallel resistors calculatorIt is relatively easy to calculate the overall resiatance of two resistors in parallel.
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ESD Antistatic Work Mats

ESD Tutorial Includes:ESD BasicsHow ESD affects electronics componentsProtecting against ESDESD protected areaESD workbenchESD work matESD wrist strapESD clothingESD storageESD processESD on a budgetDesign to combat ESDOne solution to a portable, or low cost ESD work station is to use an antistatic mat, or ESD mat.
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Decibel, dB Calculator

Decibels, dB Tutorial Includes:Decibels, dB - the basicsDecibels levels tabledBm to dBW & power conversion chartdBm to watts and volts conversion chartdB, decibel online calculatorNepersThe calculation of decibels requires the use of logarithms. Tables of other calculators may not always be available and the calculator below provides a very easy method of calculating a value in decibels from a knowledge of the input and output power levels.
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Unit of Electric Current: ampere, amp

Electric Current Tutorial Includes:What is electric currentCurrent unit - AmpereAC & DCIt is important to be able to quantify the amount of current flowing in a circuit as it enables the performance of the circuit to be defined and for the circuit to operate as required.To achieve this it is necessary to have a unit and this is the ampere or amp.
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Inductance of Straight Wire & Coils

Inductance and Transformer Tutorial Includes:InductanceSymbolsLenz& 39;s lawSelf inductanceInductive reactance calculationsInductive reactance theoryInductance of wire & coilsTransformersAlthough coils normally come to mind when thinking of inductance, a straight wire also has inductance associated with it.
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How to Choose the Best PCB Manufacturer

PCB Manufacture Includes:PCB manufacture basicsHow to choose the right PCB manufacturerIt is not always easy to choose the right manufacturer for a printed circuit board.Having developed the design for the PCB itself, the board needs to be manufactured and this is normally undertaken by a specialist PCB manufacturer.
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ITU Radio Emissions Types / Modulation Designators

The ITU, International Telecommunications Union uses an agreed set of codes or designations to easily and succinctly describe a format and modulation for a radio transmission.The designators are used by many licencing authorities around the globe including the FCC in the USA. Accordingly they are often referred to as FCC emission designators.
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RF filter design basics

RF Filters Includes:RF filters - the basicsFilter specificationsRF filter design basicsHigh & low pass filter designConstant-k filterButterworth filterChebychev filterBessel filterElliptical filterCrystal filterRF filter design is often thought to be difficult and reserved only for specialist developers.
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