AOS & LOS
Acquisition of signal is when a satellite becomes usable from your location; loss of signal is when the pass ends.
WC4DC Youth Radio Lab
Turn curiosity into a mission.
Explore satellites, hunt hidden transmitters, decode Morse, calculate antennas, build weather reports, and track a high-altitude balloon—all through short hands-on challenges.
6 missionsGuided training modulesNo account neededProgress stays in browser
01Pick a missionSpace, radio direction finding, Morse, antennas, weather, or balloon tracking
02Work the training moduleExperiment in the browser before doing the hands-on version with the club
03Build your passportComplete all six missions without creating a public youth profile
CHOOSE YOUR TRAINING MISSION
Explore. Practice. Prove it. Try it for real.
Every mission now has a learning path instead of a single mini-game. Work through Learn, Practice, Challenge, and Real-world steps. Progress is stored only in this browser.
RADIO LAB PASSPORT
Complete all six training missions.
Browser progress is private to this device and can be reset at any time.
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01 · Starter
SPACE LISTENERTalk to Space
Satellite operating combines radio, orbital motion, timing, antennas, and careful listening. This module starts with the vocabulary of a pass and ends with a planning challenge.
Elevation
Elevation describes how high the satellite appears above the horizon. A pass changes continuously from rise to set.
Follow the pass
A directional antenna is moved across the sky as the satellite travels. Operators also watch published operating information for the satellite they plan to receive.
PASS READING PRACTICE
Read a simulated satellite pass
Generate a pass, then identify where it begins, how high it gets, and where it ends. These are simulated values for learning.
MODULE SKILL CHECK
Five questions. New mix every attempt.
Score 80% or better to pass this browser checkpoint. Your best score stays on this device so you can come back and improve it.
BEST—
Ready for question 1 of 5
Start the skill check when you are ready.
TAKE IT BEYOND THE BROWSER
Real-world mission
Use the browser work as preparation, then complete the hands-on version with the right supervision, equipment, and club guidance.
- Choose a published amateur-satellite pass and write down AOS, maximum elevation, and LOS.
- With an adult or club mentor, practice pointing an antenna along the predicted path before the pass begins.
- Start by listening. Only transmit when the operator has the required amateur license and current operating information.
02 · Outdoor skill
FOX FINDERFind the Fox
Radio direction finding is a detective game: compare bearings, manage receiver sensitivity, move, repeat, and use every reading as another clue.
Compare bearings
Rotate or move the antenna and compare signal strength from several directions instead of trusting a single reading.
Too much signal
Close to the transmitter, the receiver can be overwhelmed. Direction finders often reduce sensitivity or add attenuation to keep differences visible.
Move and verify
Reflections can create false peaks. A good hunt uses more than one location and checks whether the bearing remains believable.
BEARING PRACTICE
Which direction has the strongest clue?
Take four simulated readings and choose the most likely bearing.
MODULE SKILL CHECK
Five questions. New mix every attempt.
Score 80% or better to pass this browser checkpoint. Your best score stays on this device so you can come back and improve it.
BEST—
Ready for question 1 of 5
Start the skill check when you are ready.
TAKE IT BEYOND THE BROWSER
Real-world mission
Use the browser work as preparation, then complete the hands-on version with the right supervision, equipment, and club guidance.
- Learn the boundaries and safety rules before an outdoor hunt begins.
- Take a bearing, move to a safe second location, and compare the new bearing.
- As the signal becomes very strong, practice reducing receiver sensitivity instead of simply following the loudest meter reading.
03 · Full training module
MORSE EXPLORERMorse Challenge
This is now a real training path rather than a one-letter game. Learn a small group of characters, hear them at speed, copy short strings, and move forward when accuracy is solid.
Hear the rhythm
Try to recognize the complete sound of a character instead of counting individual dits and dahs.
Accuracy first
The course records copy-drill accuracy locally in this browser. Progress comes from consistent recognition, not rushing.
Build in groups
Six WC4DC lesson groups gradually expand from a few letters to the full alphabet and numbers.
WC4DC MORSE COURSE
Six progressive lesson groups
Select a lesson. Each lesson includes all characters from the earlier lessons, so the copy pool grows as you progress.
Play a ten-character string, type what you heard, then check your copy. A score of 80% or better completes the selected lesson.
MORSE COURSE CHECKPOINT
Complete all six copy lessons.
Each lesson is completed by scoring at least 80% on its ten-character copy drill. Your lesson history and best scores stay in this browser.
TAKE IT BEYOND THE BROWSER
Real-world mission
Use the browser work as preparation, then complete the hands-on version with the right supervision, equipment, and club guidance.
- Listen for CW activity with a club member and try to recognize a few characters or a callsign.
- Practice sending only with a disconnected practice oscillator or supervised station until operating procedures are understood.
- Return to the course regularly and improve your best copy score at a comfortable speed.
04 · Build skill
ANTENNA BUILDERBuild an Antenna
The calculator is only the first step. This module connects frequency, wavelength, a simple dipole, feed point, measurement, and the basic idea of trimming a real antenna toward resonance.
Frequency ↔ wavelength
Higher frequencies have shorter wavelengths, so resonant antenna elements generally become shorter as frequency increases.
Start long, then tune
Common construction formulas are starting points. Builders normally leave a little extra wire and make small adjustments after measuring.
Measure safely
Antenna work belongs away from power lines and should be done with equipment disconnected from transmitting power while building and measuring.
ANTENNA PLANNER
Turn frequency into starting dimensions
Use common starting-point formulas for a half-wave dipole and quarter-wave element.
Build-plan checklist
- Choose a target frequency.
- Calculate and record the starting dimensions.
- Plan the center/feed point, supports, and safe mounting location.
- Leave adjustment room and measure before transmitting.
MODULE SKILL CHECK
Five questions. New mix every attempt.
Score 80% or better to pass this browser checkpoint. Your best score stays on this device so you can come back and improve it.
BEST—
Ready for question 1 of 5
Start the skill check when you are ready.
TAKE IT BEYOND THE BROWSER
Real-world mission
Use the browser work as preparation, then complete the hands-on version with the right supervision, equipment, and club guidance.
- Pick a target frequency and calculate the starting length.
- With adult/club supervision, cut and assemble a simple antenna with extra length left for tuning.
- Measure the antenna, make small adjustments, and record what changed after each adjustment.
05 · Observation skill
WEATHER DETECTIVEWeather Detective
Good emergency communication depends on clear observations. This module practices the structure of a useful report without asking anyone to approach dangerous weather.
What
Describe what was actually observed, not what a radar image or rumor suggests might be happening.
Where & when
A report becomes much more useful when it includes a clear location and a recent time.
Stay safe
The learning goal is communication, not storm chasing. Practice from a safe place using fictional scenarios or ordinary observations.
REPORT BUILDER
Practice a clear observation report
Use fictional or ordinary observations. Never go outside or approach dangerous weather to complete this activity.
MODULE SKILL CHECK
Five questions. New mix every attempt.
Score 80% or better to pass this browser checkpoint. Your best score stays on this device so you can come back and improve it.
BEST—
Ready for question 1 of 5
Start the skill check when you are ready.
TAKE IT BEYOND THE BROWSER
Real-world mission
Use the browser work as preparation, then complete the hands-on version with the right supervision, equipment, and club guidance.
- From a safe indoor location, practice describing ordinary weather in one concise sentence.
- Include location, time, and one measurable or specific detail.
- Compare your report with another student or club member and remove vague or unnecessary wording.
06 · Map & data skill
BALLOON TRACKERTrack a Balloon
A track is a story told by repeated position reports. This module turns latitude, longitude, time, and altitude into movement you can reason about.
Position reports
Latitude and longitude identify where the beacon reported from. Comparing reports reveals movement.
Altitude trend
Altitude changes over time show whether a balloon is climbing, descending, or nearly level.
Predict carefully
A simple trend can suggest the next direction, but real winds and flight behavior change. The browser challenge uses simulated data only.
TRACK READER
Turn repeated reports into movement
The coordinates and altitude below are simulated learning data, not a live aircraft or balloon.
MODULE SKILL CHECK
Five questions. New mix every attempt.
Score 80% or better to pass this browser checkpoint. Your best score stays on this device so you can come back and improve it.
BEST—
Ready for question 1 of 5
Start the skill check when you are ready.
TAKE IT BEYOND THE BROWSER
Real-world mission
Use the browser work as preparation, then complete the hands-on version with the right supervision, equipment, and club guidance.
- Open a club-approved tracking source with a mentor and identify the time, coordinates, and altitude fields.
- Compare two or more reports and describe the direction and altitude trend in plain language.
- Never enter restricted/private property or chase a payload unsafely; recovery activities require adult planning and permission.
Explore safely.
Listening is open to everyone, but transmitting on amateur frequencies requires the proper license and following FCC rules. Outdoor hunts, antenna projects, severe-weather activities, and recovery work should be done with appropriate adult supervision, permission, and safety practices.
