Parts And What I Want

This is the Jaycar-only version of the project parts list. The goal is to keep it cheap and use parts that are actually available from Jaycar.

What I Want

1. Phone Pickup Trigger

Goal:

• put my phone on a sensor
• when I take the phone off, the Pico WH plays a sound or music

Cheapest Jaycar-friendly approach:

• use a pressure sensor instead of a load cell
• the sensor sits under a small tray or phone stand
• when the phone is removed, the Pico sees the pressure drop and triggers audio

Recommended Jaycar parts:

• 1x Arduino Compatible Thin-Film Pressure Sensor XC3738
• 1x small breadboard PB8832 or PB8815
• 1x jumper kit PB8850
• 1x MP3 audio player module XC3748
• 1x microSD card XC4989 or XC4992

Notes:

• Jaycar does not appear to have the exact cheap load cell + HX711 path I would normally choose
• XC3738 is the cleanest Jaycar option for phone presence detection

2. Fly Trigger

Goal:

• detect a fly event on bait or food
• trigger a reaction

Current status:

• you already have a weight thing for the fly

Best cheap reaction options from Jaycar:

Option A: make a sound

• 1x MP3 audio player module XC3748

Option B: fast hit or flick

• 1x Standard 12V Solenoid SS0902

Why this is preferred:

• much faster than a normal micro servo
• better for a short sharp slap or flick motion
• more suitable if the goal is to hit the fly very quickly

Option C: switch an external device

• 1x 5V relay module XC4419

Important:

• do not connect the Pico directly to any high-voltage fly swatter internals
• if you ever use the swatter, the Pico should only trigger an isolated relay or another safe actuator
• the solenoid needs a separate 12V supply and a driver stage
• the moving arm should be very light so it stays fast

3. Audio / Songs

Goal:

• play songs or funny sounds
• use buttons for study, pomodoro, attack, and other actions

Best Jaycar part for this:

• 1x Arduino Compatible MP3 Audio Player with Button Controls XC3748

Why this is the right part:

• plays MP3 files from microSD
• has a built-in amplifier
• can drive an 8 ohm speaker
• has onboard buttons already
• can also be controlled over UART from the Pico

Add these:

• 1x 16GB microSD card XC4989
• 1x 32GB microSD card XC4992 if you want more audio files

Optional cheaper sound-only path:

• 1x Active Buzzer Module XC4424

Use the buzzer only if you want beeps and simple alarms. Use XC3748 if you want actual songs.

4. Buttons / Controls

Cheap button choices from Jaycar:

• 4x 6mm SPST Micro Tactile Switch SP0603

Suggested mapping:

• 1x Study
• 1x Pomodoro
• 1x Attack
• 1x Next / Stop

If you want larger nice-looking panel buttons later:

• arcade buttons like SP0664, SP0665, SP0666

5. Battery Power

Goal:

• run the Pico WH from a battery
• keep the build portable

Cheapest simple option:

• 1x 5000mAh Slim Power Bank MB3826
• 1x USB A to Micro B cable WC7757 or WC7723

This is the easiest battery option because the Pico WH can just run from USB.

Shared Jaycar Parts

• 1x Mini Breadboard - 300 holes PB8832
• or 1x 830 tie-point breadboard PB8815
• 1x Breadboard Jumper Kit PB8850
• 1x USB A to Micro B cable WC7757 or WC7723

Optional later:

• 1x Arduino Compatible 5V Relay XC4419
• 1x Standard 12V Solenoid SS0902

Cheapest First Shopping List

If buying in stages, buy these first:

• 1x Thin-Film Pressure Sensor XC3738
• 1x MP3 Audio Player with Button Controls XC3748
• 1x 16GB microSD card XC4989
• 1x Mini Breadboard PB8832
• 1x Breadboard Jumper Kit PB8850
• 4x 6mm SPST Micro Tactile Switch SP0603
• 1x 5000mAh Power Bank MB3826
• 1x Micro B USB cable WC7757 or WC7723

Buy Later If You Want Motion

• 1x Standard 12V Solenoid SS0902
• 1x 5V Relay XC4419
• 1x MOSFET
• 1x flyback diode
• 1x 12V power supply

Notes

• For songs, the XC3748 MP3 module is the correct Jaycar part to use instead of a radio setup.
• For the phone trigger, the XC3738 pressure sensor is the closest cheap Jaycar option.
• For a fast fly reaction, the SS0902 solenoid is a better fit than a normal servo.