FT8 Troubleshooting — Fix Problems Quickly and Systematically
FT8 issues are usually simple once you isolate the cause. The key is to avoid changing everything at once. Work step-by-step and verify each part of your system.
Golden Rule
Change ONE thing at a time, then test.
No Decodes (Nothing Showing)
- Check computer time sync (MOST COMMON issue)
- Confirm correct audio input device
- Verify band is active
- Check antenna and connections
Seeing Signals but No Decodes
- Time slightly off
- Audio level too low or too high
- Wrong mode or filter on radio
You Transmit but Get No Replies
- Antenna inefficiency
- RF feedback issues
- Overdriven audio (dirty signal)
- Power too low (or sometimes too high)
Contacts Start but Don’t Complete
- Timing drift
- Propagation changes
- Interference on frequency
RF Feedback Problems
- Computer glitches during transmit
- Audio distortion
- USB disconnects
Fix: improve grounding, counterpoise, and choke feedline.
Audio Issues
- No transmit → wrong output device
- No receive → wrong input device
- Distorted signal → audio too high
CAT Control Issues
- Wrong COM port
- Incorrect baud rate
- Radio not supported or misconfigured
Quick Diagnostic Flow
- Check time
- Check audio devices
- Check CAT/PTT
- Check antenna
- Test on-air
Key Takeaway
Most FT8 problems are simple once isolated. Stay systematic and avoid guessing.