Amateur radio reference for all users.
This reference app provides quick access to amateur radio band limits, country codes, band plans, radiogram messages, grid squares, and time. It also includes the RST system, Morse code, phonetic alphabet, unit abbreviations, and metric prefixes.
Showing 81–100 of 1,000 ranked alternatives.
koji kamogawa
Practice CW QSOs with real call signs
Practice amateur radio CW QSOs with realistic simulations. Choose from 599BK, Rubber Stamp, or Contest styles. Adjust call signs, signal levels, and CW speeds. Simulate pile-ups with up to three stations. Set own station parameters for CQ calls.
784767 Alberta Inc.
Look up hazard info instantly
Access hazardous material data including NIOSH, CFR/HMT, NFPA, GHS, and CAMEO information. Search, sort, and filter materials by properties or response guidelines. View emergency response guides and safety regulations for handling and storage.
Horizon Business, Inc.
Test and with quizzes
Test knowledge of U.S. and with multiple modes including , , and abbreviations. Choose difficulty and number of questions. Practice or yourself with four difficulty levels. Track statehood dates, numbers, and nicknames.
James Stuckey Weber
Look up and enter checklists
Alpha code reference allows users to look up species using four-letter . Enter to view species details. Sync with eBird checklists. Manage field notes with quick species identification.
Pretesh Patel
Access cancer staging and contouring guides
Access cancer staging guidelines, contouring atlases, and DVH normal tissue constraints. Use clinical calculators like GBM RPA. Look up commonly prescribed medications and oncology ICD9 codes. Share feedback for community improvements.
Farlex, Inc.
Find meanings by category
Allows users to search for acronyms, abbreviations, and initialisms across categories like medical, military, and technology. It provides verified meanings and enables offline searches without requiring internet access or additional downloads.
Filip Chudzinski
Browse bands, build collections, track stats
Browse official band catalogs to build and manage a collection. View stats, insights, and curated collections. Access community features and track collection progress. Explore new bands and discover curated recommendations.
Calculated Industries, Inc.
Calculate duct offsets and angles
Performs X, Y, R radius calculations and theta measurements. It includes -specific functions for ducting offsets and angle computations. Features dimensional math, geometry, and trigonometry tools for precise construction calculations.
PRESCHOOL UNIVERSITY
Learn Spanish alphabet letter sounds.
The app helps children learn Spanish alphabet letter sounds with phonetic photo images. It focuses on lowercase letters, which are more common in printed text, to provide a foundation for reading.
V PUGAZHENTHI
Calculate values instantly
Provides tools for and electronics calculations. Users can compute resistance, voltage, current, and power. Includes resistor color code conversion and voltage drop calculations aligned with NEC/IEEE standards. Supports USCS and SI units.
Roy Watson
Practice questions and track progress
Review official Class FCC questions and answers. Take quizzes by topic and full practice exams. Track performance and progress over time. Study for the license with structured practice and feedback.
MY TOWN GAMES LTD
Explore floors, play games, learn together
Explore a virtual with 6 themed floors. Play laser tag, relax in an arcade room, or join a music band. Discover interactive rooms and characters. Unlock new stories with each visit. Move characters between locations.
Adam Birdsall
Aviation tool for airport codes
The app provides a reference for aviation terms and airport codes. It allows users to search hundreds of abbreviations and thousands of airport codes with cloud-integrated data.
Nicolas Associates Ltd
Worldwide repeater directory, free access.
The app provides a worldwide repeater directory with comprehensive search and sorting capabilities. It displays distance, heading, and full repeater details without requiring a network connection.
Julian Tigler
Send secret messages with ciphers
Send encrypted messages using historical ciphers like A1Z26, Caesar Shift, and Vigenere. Encrypt text with customizable settings. Share coded messages via text or email. Decode messages using the same methods. View details and instructions.
Sergey Vavaev
Access theory, diagrams, and calculators offline
’s provides access to electrical theory topics, including exercises with answers. Features interactive diagrams for hands-on learning. Includes calculators and formulas for electrical calculations. Works offline without ads or subscriptions.
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