- Work in a clean, well-lit area
- Keep workspace clear of liquids
- Have adequate lighting for detailed work
- Ensure stable work surface
- Keep food and drinks away from workspace
- Wash hands after handling components
- CRITICAL: Verify correct power supply voltage and polarity before connecting
- Required: TODO V DC, TODO mA minimum current
- Use only DC power supply with correct voltage rating
- Check polarity markings on board bottom before connecting
- Ensure JST connector is properly keyed and oriented
Board-Specific:
- Power connectors are on board edges (JST type)
- Polarity markings visible on bottom of board
- LED (D2) should illuminate when power is correctly applied
- If LED doesn't light, immediately disconnect and check polarity
IMPORTANT: Components are polarity-sensitive:
- Power Connections: JST connectors are keyed but always verify orientation
- Check board bottom for polarity markings (+ and -)
- Match cable colors if standardized (typically red = positive, black = negative)
- Reversed polarity can destroy FM radio IC and other components
- Speaker Connection (SPK): Observe polarity if speaker is marked
- Reversed speaker polarity affects audio quality but typically won't damage components
- Check speaker and board markings before connecting
Visual Verification:
- Look at bottom side of board for connector polarity labels
- Match connector key orientation with board socket
- Verify LED illuminates with correct brightness after power-on
- Disconnect power before making circuit modifications
- Use multimeter to verify voltages before applying power:
- Power input should measure TODO V DC
- Check polarity: positive probe to +, negative to -
- Watch for component heating during initial power-on:
- FM radio IC should remain cool to warm
- Potentiometers should not get hot
- LED (D2) may be slightly warm (normal)
- Be prepared to quickly disconnect power if:
- LED doesn't light
- Components get excessively hot
- You smell burning
- You hear unusual sounds
Note: If this kit uses batteries:
- TODO: Battery type and specifications
- Install batteries with correct polarity
- Remove batteries if kit will not be used for extended periods
- Do not mix old and new batteries
- Dispose of batteries properly according to local regulations
- Do not short circuit, puncture, or incinerate batteries
Li-Ion Battery Warning (if applicable):
- Li-Ion batteries can be dangerous if mishandled
- Never exceed rated charging voltage/current
- Use only approved chargers
- Do not over-discharge
- Watch for swelling, damage, or heating
- Store in cool, dry place away from flammable materials
¶ Component Handling
¶ Board Handling
- Static Protection: While board has protection, minimize ESD risk
- Hold board by edges when possible
- Avoid touching component pins and IC leads
- Store in anti-static bag when not in use
- Do not force rotation beyond mechanical stops
- Turn gently and smoothly
- Volume and tuning controls have limited rotation range
- Forcing past stops can damage internal mechanism
- JST Connectors:
- Should insert smoothly with gentle pressure
- Will click when fully seated
- Never force connector - if it doesn't fit, check orientation
- To remove: squeeze locking tabs and pull gently (if applicable)
- Damaged connectors can cause intermittent connections or shorts
- Status LED (D2):
- Should glow but not be excessively bright
- Slightly warm temperature is normal
- If LED is very hot, disconnect power immediately
- Looking directly at bright LED can cause eye discomfort
- Volume Control:
- Always start with volume at minimum
- Increase gradually to desired level
- Excessive volume can damage speaker or cause hearing damage
- Use appropriate speaker impedance (TODO ohms)
- Speaker should not vibrate excessively or distort
Static-sensitive components require ESD precautions:
- FM radio IC (U1) is static-sensitive
- Use ESD wrist strap when available
- Touch grounded metal object before handling board
- Store board in ESD-safe packaging
- Avoid touching exposed pins and IC leads
- Work on non-static-generating surfaces (avoid plastic, synthetic fabrics)
- Disconnect power before touching victim
- Call emergency services
- Begin CPR if qualified and necessary
- Emergency Services: TODO
- Poison Control: TODO
- Dispose of electronic components according to local e-waste regulations
- Do not dispose of batteries in regular trash
- Recycle PCBs and components when possible
Remember: When in doubt, ask for help. Safety is more important than speed.
Last Updated: TODO
Revision: See Revision Notes