GROL Exam Prep & Band Plan

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GROL Prep is the exam trainer, reference and calculator set a radio operator reaches for at the bench, in the truck, or at sea with no signal — encoded from the current FCC rules and the standard handbook formulas.

BAND PLAN
• Every US amateur band from 160 meters to 23 centimeters, drawn as a bar you can read at a glance.
• Pick Technician, General or Amateur Extra and see exactly where you may transmit, in what modes, at what power — from 47 CFR Part 97, with the section cited on every segment.
• Tap any frequency to see who may use it and what convention applies there.
• The voluntary ARRL band-plan conventions and calling frequencies, clearly labelled as conventions rather than rules.
• Includes the December 2025 changes to 60 meters.

FCC EXAM PREP
• The complete question pools the FCC publishes for its commercial radio operator examinations: Element 1 (Marine Radio Operator Permit), Element 3 (General Radiotelephone, the GROL), Element 6 (Radiotelegraph), Elements 7 and 7R (GMDSS Operator and Restricted), Element 8 (Ship Radar Endorsement) and Element 9 (GMDSS Maintainer).
• 2,859 questions with every figure, reproduced exactly, with each pool's approval date on its page.
• Practice exams built the way a COLEM builds the real one: the real length, the real pass mark, one question drawn from each key topic, timed.
• Spaced repetition on what you miss, flashcards, and a straight readiness estimate per element.
• Element 1, the Marine Radio Operator Permit pool, is free forever. One payment of $14.99 unlocks Elements 3, 6, 7, 7R, 8 and 9. Not a subscription; nothing else to buy.

REFERENCE
• Q-codes in both question and statement forms, searchable by meaning ("location" finds QTH).
• RST signal reports with a decoder: type 579, read what it means.
• CW abbreviations and prosigns, with the Morse.
• The ITU phonetic alphabet, with a callsign speller: type W1AW/7, read or hear "Whiskey One Alfa Whiskey Stroke Seven".
• The three ITU regions and what they mean for a US operator.

ANTENNA CALCULATORS
• Half-wave dipole, inverted V, quarter-wave vertical with radials, full-wave loop (square, delta or circle) and J-pole.
• Frequency in, lengths out in feet-and-inches and metric, with adjustable end-effect constant and wire velocity factor.
• Every calculator shows its formula and its assumptions. Cut long and trim.

RF MATH
• dB to power and voltage ratio and back; dBm to watts and back.
• SWR from forward and reflected power; return loss, mismatch loss and reflected power for any SWR.
• Coax loss for 15 common lines (RG-58, RG-8X, RG-213, LMR-400, Heliax, ladder line and more) at any frequency and length, with the power reaching the antenna.
• ERP and EIRP from transmitter power, feedline loss and antenna gain.

SAVED AND EXPORT
• Save any calculation with its inputs; bookmark any code, band or abbreviation. Export saved work, bookmarks, exam progress and exam history as CSV or JSON.

PRIVATE BY CONSTRUCTION
The app has no server of its own and requests no permissions. The only network traffic it can make is the App Store's own, when you buy or restore. Everything you enter stays on your device.

GROL Prep is a reference. 47 CFR Part 97 as published by the FCC is the only authority on what you may transmit. The band plan was encoded from the eCFR text on the date shown in Settings, and the FCC changes it from time to time. ARRL is a registered trademark of the American Radio Relay League, Inc., which is not affiliated with and does not endorse this app.

The examination question pools are works of the United States Government and are not subject to copyright. Most date from 2009 to 2021 and are nonetheless the pools in force; confirm with your COLEM that no newer pool has been adopted before you sit. Practice exam scores estimate readiness, they do not predict a result. Not affiliated with, endorsed by, or associated with the FCC or any COLEM.