The Toolbox
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Marine VHF channelsCh 16, 13, 22A, 70 and the restOhm's law calculatorAny two values give the thirdVSWR calculatorFrom forward and reflected powerResistor color codeBands to ohms and tolerancePhonetic alphabet & codesAlpha to Zulu, Q codes, squawk codesAviation frequenciesGuard, ATIS, CTAF, ILS and more
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CalculatorsRF, electrical, fiber, radar, flight and metrology calculators.35 calculatorsFrequency ReferenceMarine, aviation, amateur, personal radio, SAR and telemetry frequencies.6 frequency listsQuick Reference ChartsResistor color code, wire gauge, coax, connectors, batteries, codes.11 chart setsTroubleshooting GuidesSymptom-to-fix guides for marine, aviation, RF, fiber, power and drones.7 guidesStandards & SpecsFCC, FAA, IEC and NAR figures for marine, aviation, RF and fiber.8 referencesFormula ReferenceOhm's law, power, reactance, dB, time constants, radar, antennas.91 formulasSchematics & DiagramsSchematic symbols, logic gates, block diagrams, antenna patterns.5 symbol setsGlossaryPlain-English definitions across RF, avionics, marine radio and more.484 termsTest EquipmentGuides to the IFR 4000, thermal imagers and spectrum analyzers.3 instruments