Project-related notes
Start here when you want a note that supports a project path directly.
Linux Command Line Foundations for Makers
Purpose: Open a terminal, find files, read output, and run small inspection commands with confidence.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Learn enough shell navigation, reading, and command composition to inspect a project machine without blindly pasting commands. Open a terminal, find files, read output, and run small inspection commands with confidence. pwd, ls, and cat tell you where you are and what file you are reading before you change anything. Create a small folder with two text files. Use pwd, ls -lah, head, and grep to answer where the files are and what each contains. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Nginx Static Site Basics for Makers
Purpose: Understand the path from a local HTML file to a live HTTPS page on a VPS.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Learn how Nginx serves a static site from a document root, why release folders help, and how to verify a deploy safely. Understand the path from a local HTML file to a live HTTPS page on a VPS. nginx -t proves configuration syntax before reload. Sketch a release layout with releases/YYYYMMDDTHHMMSSZ and current. Explain how rollback would work. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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DNS Records and SSL for Makers
Purpose: Connect a domain to a VPS without guessing whether the problem is DNS, Nginx, or TLS.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Learn the practical order for pointing a domain at a VPS, checking DNS, proving HTTP, and adding HTTPS. Connect a domain to a VPS without guessing whether the problem is DNS, Nginx, or TLS. dig +short domain A shows the public A record answer. Write the sequence you would use to connect a new domain to an existing VPS, including the command that proves each step. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Linux Files and Permissions for Makers
Purpose: Diagnose why a project file cannot be read, executed, or served.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Learn paths, owners, groups, modes, and parent directory traversal before changing chmod or chown. Diagnose why a project file cannot be read, executed, or served. namei -l /path/to/file walks every path component. Build a test directory where only the parent execute bit is wrong. Use namei -l to identify the break. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build. If the next command, measurement, diagram, or sketch feels unclear, pause and write that question before moving on.
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Search Logs with grep, find, and tail
Purpose: Find the relevant log lines for a recent failure without reading the whole log directory.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Learn how to search project logs by scope, time, and symptom so debugging starts from evidence. Find the relevant log lines for a recent failure without reading the whole log directory. tail -80 logfile reads a bounded slice before deeper searching. Given a failing service name, list three bounded commands you would run before opening a huge log. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Git Workflow for Small Projects
Purpose: Make a small project safer to edit, deploy, and roll back.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Use Git to inspect changes, commit one idea at a time, tag releases, and keep rollback possible. Make a small project safer to edit, deploy, and roll back. git status shows what changed before you commit or deploy. Change one line in a sample file, inspect it with git diff, stage it, and write a commit message that describes only that change. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Linux Disk Space and Logs for Makers
Purpose: Identify whether a disk-full problem is bytes, inodes, journal logs, Docker, or deleted-open files.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Learn how bytes, inodes, logs, and deleted-open files can each make a project machine look full. Identify whether a disk-full problem is bytes, inodes, journal logs, Docker, or deleted-open files. df -h and df -i separate byte pressure from inode pressure. Write a five-command disk-full triage checklist and explain what each command proves. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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SSH Keys and Known Hosts for Makers
Purpose: Debug SSH access without exposing private keys or blindly removing known_hosts entries.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Learn how SSH identity, authorized keys, host keys, and file modes fit together before deleting warnings. Debug SSH access without exposing private keys or blindly removing known_hosts entries. ssh -vvv user@host shows which authentication step fails. Describe how you would tell apart a publickey failure from a changed host key warning. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Python Virtual Environments for Makers
Purpose: Run a project with the intended Python interpreter and dependency set.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Learn why Python projects use virtual environments and how to prove which interpreter and packages are active. Run a project with the intended Python interpreter and dependency set. python -V and which python show which interpreter your shell will use. Create a tiny venv, install one package, and prove which python and pip are active. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Godot First Playable Loop
Purpose: Create a tiny game loop with input, movement, collision, a goal, and reset.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Build the smallest playable loop before adding art, menus, inventory, or online systems. Create a tiny game loop with input, movement, collision, a goal, and reset. Write the player action in one sentence before adding systems. Make a one-room prototype where a test player reaches a goal and resets. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build. If the next command, measurement, diagram, or sketch feels unclear, pause and write that question before moving on.
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Sprite-Animated 2D Game Loop
Purpose: Create one playable 2D proof with animated player states, tile collision, a goal, and a repeatable export check.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Build a tiny Godot 4 scene where one sprite moves, animates, collides with a tile room, reaches a goal, and resets. Create one playable 2D proof with animated player states, tile collision, a goal, and a repeatable export check. Write the verb, sprite states, tile size, and one-room proof before adding art polish or extra mechanics. Use the widget to choose frames, FPS, tile size, room size, and movement speed. Copy the note, then make one Godot scene that proves those numbers. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Tilemap Level Layout Math
Purpose: Sketch and build a one-room Godot tilemap where the player can see the route, collide with solid cells, reach a goal, and explain the scale.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use tile size, room dimensions, camera view, collision cells, and traversal time to design one readable 2D room before painting a large map. Sketch and build a one-room Godot tilemap where the player can see the route, collide with solid cells, reach a goal, and explain the scale. Write tile size, viewport size, room tile count, solid/passable cell rules, and one route before decorating the map. Use the widget to choose tile size, room dimensions, viewport size, and movement speed. Copy the note, then build one room with floor, wall, gap, goal, and camera limits.
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Collision Normal Bounce Math
Purpose: Build a one-wall Godot bounce proof where incoming velocity, collision normal, outgoing velocity, and energy loss are visible.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use vectors, surface normals, and restitution to make one 2D bounce predictable before building a whole physics-heavy game. Build a one-wall Godot bounce proof where incoming velocity, collision normal, outgoing velocity, and energy loss are visible. Sketch one contact: incoming arrow, surface normal, reflected arrow, and the value that proves the bounce is repeatable. Use the widget to choose incoming velocity, normal angle, and restitution. Copy the note, then reproduce one wall bounce in a tiny Godot scene. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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2D Transform Stack for Sprites
Purpose: Place one child sprite from a local offset, predict its world position, and explain why parent rotation or scale moved it.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use local space, parent transforms, rotation, scale, and pivot checks to place sprite attachments without dragging things by eye. Place one child sprite from a local offset, predict its world position, and explain why parent rotation or scale moved it. Create one parent marker and one child sprite, then write the child's local offset before changing the parent transform. Use the widget to choose a parent transform and child local offset. Copy the note, then build one parent marker and child sprite in Godot. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Projectile Arc Tuning for Godot
Purpose: Build a one-launch Godot proof where the predicted arc, actual projectile path, first hit, and tuning notes can be compared.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use launch angle, speed, gravity, and time steps to sketch a projectile arc before tuning a cannon, thrown item, jump shot, or ball path by feel. Build a one-launch Godot proof where the predicted arc, actual projectile path, first hit, and tuning notes can be compared. Sketch one launch point, one target, one gravity value, and one time window before adding effects or enemies. Use the widget to choose angle, speed, gravity, and time. Copy the note, then build one projectile scene and compare the preview arc to the actual hit. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Microcontroller Wiring First Checks
Purpose: Inspect a simple controller circuit with less guesswork and fewer fried parts.
Related project or ladder: Wire a Sensor to a Microcontroller · Source ladder
Learn the first checks before blaming firmware: power, ground, pin mapping, signal direction, and measurement points. Inspect a simple controller circuit with less guesswork and fewer fried parts. Disconnect power before changing wiring, then verify voltage before connecting a device. Draw a three-wire sensor connection and mark power, ground, signal, expected voltage, and measurement point. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Hydraulic Schematic First Read
Purpose: Explain what a basic hydraulic circuit is trying to do before touching equipment.
Related project or ladder: Read a Hydraulic Schematic · Source ladder
Learn a first-pass method for reading hydraulic schematics: source, actuator, valve, flow path, pressure limit, and safe stop. Explain what a basic hydraulic circuit is trying to do before touching equipment. Identify the energy source and stored-energy hazards before tracing the circuit. On a simple cylinder circuit drawing, mark pump, tank, valve, actuator, relief, extend path, and retract path. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Godot Input Actions First Pass
Purpose: Make input remapping and controller support easier later.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Map player intent to actions before wiring controls directly to keys. Make input remapping and controller support easier later. Create action names before binding keys. Create a small practice case for godot input actions first pass and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build. If the next command, measurement, diagram, or sketch feels unclear, pause and write that question before moving on.
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Godot Collision Debugging Basics
Purpose: Debug a small collision problem without rewriting the whole player controller.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Find why game objects pass through, stick, or never trigger collisions. Debug a small collision problem without rewriting the whole player controller. Turn on visible collision shapes before changing physics code. Create a small practice case for godot collision debugging basics and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Game Save System First Draft
Purpose: Save and reload one small game state without inventing a full account system.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Plan the first save file around the minimum state needed to resume a prototype. Save and reload one small game state without inventing a full account system. List the exact state that must survive closing the game. Create a small practice case for game save system first draft and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Multimeter First Measurements
Purpose: Use a meter to answer a circuit question instead of guessing.
Related project or ladder: Wire a Sensor to a Microcontroller · Source ladder
Learn the first safe multimeter checks: voltage, continuity, resistance, and current caution. Use a meter to answer a circuit question instead of guessing. Set the meter mode before touching the probes to the circuit. Create a small practice case for multimeter first measurements and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Read a Datasheet First Pass
Purpose: Find voltage, pinout, absolute maximums, and typical application notes.
Related project or ladder: Wire a Sensor to a Microcontroller · Source ladder
Extract the first useful facts from a component datasheet without reading every page. Find voltage, pinout, absolute maximums, and typical application notes. Find the part number and package before trusting a pinout. Create a small practice case for read a datasheet first pass and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Motor Driver First Checks
Purpose: Bring up a small motor driver safely enough to test direction and speed.
Related project or ladder: Wire a Sensor to a Microcontroller · Source ladder
Check power, ground, enable pins, signal voltage, and load wiring before blaming firmware. Bring up a small motor driver safely enough to test direction and speed. Disconnect the motor until logic power and driver wiring are understood. Create a small practice case for motor driver first checks and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Stepper Motor Wiring First Checks
Purpose: Wire a small stepper motor without randomly swapping leads.
Related project or ladder: Wire a Sensor to a Microcontroller · Source ladder
Identify stepper coil pairs, driver connections, current limits, and direction before tuning motion. Wire a small stepper motor without randomly swapping leads. Find the two coil pairs before connecting the driver. Create a small practice case for stepper motor wiring first checks and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Hydraulic Cylinder Leak First Checks
Purpose: Describe a cylinder leak clearly before ordering parts or disassembling equipment.
Related project or ladder: Read a Hydraulic Schematic · Source ladder
Separate external seal leaks, fitting leaks, hose damage, and internal bypass symptoms. Describe a cylinder leak clearly before ordering parts or disassembling equipment. Depressurize and make the equipment safe before inspection. Create a small practice case for hydraulic cylinder leak first checks and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Hydraulic Pressure vs Flow
Purpose: Explain why a slow actuator and a weak actuator are not the same symptom.
Related project or ladder: Read a Hydraulic Schematic · Source ladder
Understand the difference between pressure, flow, force, and speed in a hydraulic system. Explain why a slow actuator and a weak actuator are not the same symptom. Identify whether the complaint is force, speed, heat, or noise. Create a small practice case for hydraulic pressure vs flow and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Make an Obsidian Project Note
Purpose: Keep one project note that actually helps you resume work.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Turn a project idea into a reusable note with goal, prerequisites, sources, decisions, and next action. Keep one project note that actually helps you resume work. Write the next physical or technical action in one sentence. Create a small practice case for make an obsidian project note and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Turn a Video into Flashcards
Purpose: Make five review cards that preserve the useful lesson from a video.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Convert a useful video into notes and cards without copying noise. Make five review cards that preserve the useful lesson from a video. Watch for decisions, warnings, and output interpretation, not just vocabulary. Create a small practice case for turn a video into flashcards and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Read a Project Error Message
Purpose: Stop treating every error message as a wall of text.
Related project or ladder: Deploy a Static Site on a VPS · Source ladder
Break an error into location, cause, expected state, and next test. Stop treating every error message as a wall of text. Copy the exact first error line and the command that produced it. Create a small practice case for read a project error message and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Supporting ladder notes
Use these notes when a project exposes a more specific concept, tool, or safety question.
CAD Constraints First Sketch
Purpose: Create a simple sketch that survives later changes.
Related project or ladder: Build an Obsidian Project Notebook · Source ladder
Use constraints and dimensions to make a sketch editable instead of fragile. Create a simple sketch that survives later changes. Define the design intent before adding every dimension. Create a small practice case for cad constraints first sketch and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build. If the next command, measurement, diagram, or sketch feels unclear, pause and write that question before moving on.
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Measure Fastener Threads
Purpose: Avoid mixing similar-looking fasteners that do not actually fit.
Related project or ladder: Build an Obsidian Project Notebook · Source ladder
Identify diameter, pitch, length, and head style before ordering or replacing a fastener. Avoid mixing similar-looking fasteners that do not actually fit. Clean and inspect the fastener before measuring it. Create a small practice case for measure fastener threads and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build. If the next command, measurement, diagram, or sketch feels unclear, pause and write that question before moving on.
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Welding First Safety Checklist
Purpose: Prepare a safe practice weld area before learning bead control.
Related project or ladder: Build an Obsidian Project Notebook · Source ladder
Walk through PPE, ventilation, fire watch, material prep, and machine setup before striking an arc. Prepare a safe practice weld area before learning bead control. Confirm PPE, ventilation, and nearby combustibles before power-on. Create a small practice case for welding first safety checklist and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Robot Drivetrain First Prototype
Purpose: Drive a platform forward, backward, and turn reliably.
Related project or ladder: Build an Obsidian Project Notebook · Source ladder
Build the smallest drivetrain test before adding sensors, autonomy, or payload. Drive a platform forward, backward, and turn reliably. Test motors off the ground before adding load. Create a small practice case for robot drivetrain first prototype and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build. If the next command, measurement, diagram, or sketch feels unclear, pause and write that question before moving on.
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Sensor Mounting First Pass
Purpose: Mount a sensor so it can produce useful readings after the robot moves.
Related project or ladder: Build an Obsidian Project Notebook · Source ladder
Plan sensor field of view, vibration, cable strain, and calibration access before printing brackets. Mount a sensor so it can produce useful readings after the robot moves. Write what the sensor must see before designing the bracket. Create a small practice case for sensor mounting first pass and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Small Engine No-Start First Checks
Purpose: Describe a no-start problem in evidence terms.
Related project or ladder: Build an Obsidian Project Notebook · Source ladder
Use a basic fuel, spark, air, and safety-interlock sequence before replacing parts. Describe a no-start problem in evidence terms. Make the machine safe and follow the manual before inspection. Create a small practice case for small engine no-start first checks and write what each step proves before moving to the next one. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Packet Radio with a Baofeng: Receive-First APRS Basics
Purpose: Draw a receive-first packet-radio path and explain what a decoded packet proves without assuming transmit permission.
Related project or ladder: Learn the command line for maker projects · Source ladder
Understand packet radio and APRS with a Baofeng-class handheld by mapping the radio, audio path, decoder, packet fields, and license boundary before any transmit work. Draw a receive-first packet-radio path and explain what a decoded packet proves without assuming transmit permission. Start receive-only: identify the radio role, audio path, decoder, expected packet fields, and local rules before touching transmit. Draw a packet path for a receive-only Baofeng/APRS learning setup. Label radio, audio interface, decoder, packet fields, license boundary, and the exact point where you stop before transmit. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Antenna Length Math for Makers
Purpose: Convert frequency into wavelength fractions, compare meters/feet/inches, apply a velocity factor, and explain why the result is only a starter estimate.
Related project or ladder: Learn the command line for maker projects · Source ladder
Estimate wavelength, quarter-wave, and half-wave starter lengths from frequency before changing antennas, cutting wire, or trusting a build video. Convert frequency into wavelength fractions, compare meters/feet/inches, apply a velocity factor, and explain why the result is only a starter estimate. Stay receive-first unless you have the right authorization. Write frequency, units, antenna type, and tuning check before any transmit use. Enter one frequency into the calculator, copy the estimate note, then write full-wave, half-wave, quarter-wave, velocity factor, and the next verification step before any real build. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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RSSI Mapping for Direction Finding
Purpose: Record angle/RSSI pairs, plot a strongest lobe, and explain what the reading suggests without claiming exact source location.
Related project or ladder: Learn the command line for maker projects · Source ladder
Use receive-only signal-strength readings to sketch a direction clue, compare angles, and explain uncertainty before making any field claim. Record angle/RSSI pairs, plot a strongest lobe, and explain what the reading suggests without claiming exact source location. Use only lawful receive-only readings from your own test source or a signal you are allowed to monitor; do not track people or interfere with equipment. Enter eight angle/RSSI pairs in the widget, copy the Markdown note, then write whether the strongest direction is a clean peak, a broad lobe, or too noisy to trust. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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SDR Flight Tracking: ADS-B First Pass
Purpose: Name the ADS-B frequency, antenna role, receiver role, decoded fields, and map output without confusing receive-only learning with official tracking or transmitting.
Related project or ladder: Learn the command line for maker projects · Source ladder
Use an RTL-SDR-style receiver to understand public ADS-B aircraft broadcasts: frequency, antenna, receiver, decoder, fields, map display, and the receive-only boundary. Name the ADS-B frequency, antenna role, receiver role, decoded fields, and map output without confusing receive-only learning with official tracking or transmitting. Stay receive-only. Identify the signal type, 1090 MHz frequency, antenna, receiver, decoder, field list, and lawful-use boundary before installing or sharing anything. Draw one receive-only ADS-B path. Label aircraft broadcast, 1090 MHz signal, antenna, RTL-SDR, decoder, decoded fields, map display, timestamp, and the limits of your claim. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Stepper Antenna Sweep for Direction Finding
Purpose: Build a repeatable sweep plan: angle steps, antenna orientation, RSSI sample, strongest lobe, repeated run, and uncertainty note.
Related project or ladder: Learn the command line for maker projects · Source ladder
Connect trigonometry, a rotating fixture, and receive-only RSSI readings so a maker can sweep an antenna in known steps and write an honest bearing clue. Build a repeatable sweep plan: angle steps, antenna orientation, RSSI sample, strongest lobe, repeated run, and uncertainty note. Start receive-only with a lawful test signal and a hand sketch of the rotation before wiring a motor or making a location claim. Make a 12-stop sweep table at 30-degree increments. Sketch the arm, write two example RSSI runs, mark the strongest lobe, and explain what remains uncertain. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Motion Tracking with Vector Velocity
Purpose: Compare two positions, compute the delta vector, divide by elapsed time, and explain speed and direction without hiding units or uncertainty.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Turn two position samples into direction, speed, and a useful motion note for games, robots, camera tracking, or sensor logs. Compare two positions, compute the delta vector, divide by elapsed time, and explain speed and direction without hiding units or uncertainty. Write the two positions, units, and elapsed time before calculating speed or smoothing the track. Enter a current point, target point, and speed in the graph widget. Then write the delta vector, length, unit direction, next position, and what extra samples you would need before trusting the motion. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Basic Statistics for Sensor Logs
Purpose: Read a short sensor log and explain mean, median, range, standard deviation, outliers, and moving-average tradeoffs in project terms.
Related project or ladder: Build an Obsidian project notebook · Source ladder
Turn repeated maker readings into a small evidence note: typical value, noise width, suspicious jumps, and what to measure again. Read a short sensor log and explain mean, median, range, standard deviation, outliers, and moving-average tradeoffs in project terms. Keep the raw readings and units before smoothing, deleting, or explaining away a weird value. Take ten sample readings from a sensor, RSSI sweep, temperature probe, or simulated list. Write the mean, median, min, max, range, one suspicious reading, and the next repeat test. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Vectors for Maker Projects
Purpose: Describe a movement, force, sensor direction, or offset as a vector and explain what the numbers mean.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use vectors as arrows with size and direction so game movement, sensor orientation, force sketches, and layout offsets become inspectable. Describe a movement, force, sensor direction, or offset as a vector and explain what the numbers mean. Draw the arrow first: start point, direction, length, and units before writing formulas or code. Sketch a small game object moving toward a target. Label current position, target position, direction vector, length, and unit direction. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Dot Product for Facing and Projection
Purpose: Use dot product as a yes/no or how-much signal for facing, projection, lighting, and control problems.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use dot product to answer practical questions: is one thing facing another, how much motion points forward, or how much light hits a surface. Use dot product as a yes/no or how-much signal for facing, projection, lighting, and control problems. Normalize direction vectors first when you want an angle-like comparison instead of a size-weighted number. Draw a player forward arrow and a target direction arrow. Predict whether the dot product should be positive, near zero, or negative before calculating it. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Trigonometry for Rotation and Layout
Purpose: Move between an angle, a side length, and a coordinate change without guessing.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use sine, cosine, tangent, radians, and atan2 to turn angles into positions, rotations, slopes, and repeatable layout checks. Move between an angle, a side length, and a coordinate change without guessing. Write whether the angle is in degrees or radians before using it in code, calculators, or sketches. Draw a rotating pointer, mark radius and angle, then compute where the tip should be for one simple angle. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Calculus for Game Motion
Purpose: Connect position, velocity, acceleration, and frame time so a motion change can be predicted before it is tuned.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use slope, velocity, acceleration, area, and frame time to reason about game motion before tuning jumps, slides, camera movement, projectiles, or drone-style motion values. Connect position, velocity, acceleration, and frame time so a motion change can be predicted before it is tuned. Write the axis, units, starting position, velocity, acceleration, and time step before changing a physics value. Use the widget with one jump or slide example. Change acceleration once, predict the graph, then copy the note and explain whether velocity or position changed first. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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FFT Frequency Peaks First Pass
Purpose: Compare a time signal with a frequency view and identify one dominant repeating pattern.
Related project or ladder: Build an Obsidian project notebook · Source ladder
Use a simple FFT-style frequency view to spot repeated patterns in audio, vibration, motor, sensor, or SDR-like logs without overclaiming the cause. Compare a time signal with a frequency view and identify one dominant repeating pattern. Write the sample rate, units, recording length, sensor or source, and expected pattern before reading frequency peaks. Use the widget to create two tones, change sample rate once, copy the note, and explain which peak is useful and what remains uncertain. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action.
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Audio Spectrum Visualizer with FFT
Purpose: Build a first-pass spectrum visualizer plan: source signal, sample rate, FFT bins, bar display, peak clue, and uncertainty note.
Related project or ladder: Build an Obsidian project notebook · Source ladder
Use FFT thinking to turn microphone, file, game-audio, or sensor samples into frequency bars without pretending the display proves more than it does. Build a first-pass spectrum visualizer plan: source signal, sample rate, FFT bins, bar display, peak clue, and uncertainty note. Write the audio or sensor source, sample rate, window length, units, display goal, and what the bars should not claim. Use the widget to make two tones and one noise note. Copy the visualizer note, then sketch a Godot, Python, or microcontroller display path with source, sample rate, bars, peak clue, and next repeat test.
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Scale, Ratio, and Unit Conversions
Purpose: Convert a drawing, measurement, or material estimate into the units the project actually needs.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use ratios, scale factors, and unit conversions to move between drawings, material lists, sensor readings, and real dimensions. Convert a drawing, measurement, or material estimate into the units the project actually needs. Write the starting unit and target unit before multiplying anything. Convert one small project dimension from a sketch into real size, then write the estimate, exact conversion, and a named tolerance. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Interpolation for Motion and Controls
Purpose: Explain what start value, end value, and progress value produce a smooth transition.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use interpolation to move between two values in a controlled way: animation, smoothing, servo targets, UI sliders, and parameter changes. Explain what start value, end value, and progress value produce a smooth transition. Name the start, end, and progress value before choosing lerp, easing, or smoothing. Animate a number from 0 to 100 and write what t=0, t=0.25, t=0.5, and t=1 should produce before testing it. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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Geometry for Cuts, Clearance, and Fit
Purpose: Check a physical layout with diagonals, offsets, spacing, and clearance before making a permanent cut.
Related project or ladder: Build a First Godot Game Loop · Source ladder
Use simple geometry to reason about square corners, clearances, hole spacing, diagonal checks, and parts that need to fit before cutting material. Check a physical layout with diagonals, offsets, spacing, and clearance before making a permanent cut. Sketch the part and mark fixed edges, clearance zones, and measurement points before measuring diagonals. Draw a rectangular panel with two holes. Mark the reference edge, centerline, hole spacing, clearance, and diagonal check. Keep the note tied to a concrete maker project so the lesson does not become a saved link with no next action. After reading, choose one related lesson or practice task and produce a small proof that the idea works in your build.
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