AMRT — Ham Radio Toolkit

The field-ready toolkit for amateur radio operators. Build antennas, tune feedlines, and look up the references you need — fast, accurate, and fully offline.

AMRT puts the math you actually use in the shack and in the field into one clean, dark-mode app. Every calculator shows its formula and assumptions, so you always know exactly what it computed and why.

ANTENNA & FEEDLINE CALCULATORS
• Dipole, inverted-V, vertical, and end-fed half-wave lengths
• Yagi, cubical quad, J-pole, and magnetic loop designs
• Wavelength ↔ frequency, with quarter- and half-wave taps
• VSWR, return loss, mismatch loss, and reflection coefficient
• Coax velocity factor, electrical length, and loss
• Resistor color codes and series/parallel networks
• Maidenhead grid square from coordinates or GPS

PRACTICAL BUILDER FEATURES
• Results in meters, feet-and-inches, or fractional inches (to 1/8, 1/16, 1/32)
• Save any calculation and reopen it later — values restored exactly
• Pin your favorite tools and jump back to recent ones from Home
• Home screen widget for your callsign, grid square, and UTC clock

QUICK REFERENCES, ALWAYS OFFLINE
• Q codes, the NATO phonetic alphabet, and Morse code
• Band plans and coax cable specifications

BUILT FOR THE FIELD
• Works with no signal — calculators, references, saved work, and projects are all offline
• Permanently dark, easy on the eyes at the operating position
• Accessibility: adjustable text size, high-contrast mode, and VoiceOver support

A one-time PRO unlock opens the full tool library. No subscriptions, no ads in the calculators, and Restore Purchase is always available.

73 and good DX!