Troubleshoot Weak Upload Signal
If calls connect but the other side can’t hear you well, work through this quick checklist.
1) Check donor signal quality
- Measure RSRP and SINR outdoors near the donor antenna position.
- If SINR is poor (< 0–2 dB), use a directional LPDA and re‑aim.
2) Confirm isolation
Feedback between indoor and outdoor antennas can throttle uplink gain.
- Increase separation and turn donor away from indoor antennas.
- Use building mass (roof, walls) as a shield.
3) Cable and connectors
- Prefer LMR400 for long runs; avoid damaged or water‑logged connectors.
- Each adapter adds loss; simplify the chain.
4) Device/network edge cases
- Phones at the far edge of coverage might hit time advance limits; move indoors closer to the antenna.
- Lock LTE/VoLTE if 3G fallback causes issues (device‑specific).
5) Test method
- Place a steady upload (speed test) while adjusting antenna aim.
- Record before/after RSRP and SINR; seek higher SINR even if RSRP drops a bit.
Bottom line: Uplink quality follows donor quality + isolation. Fix those first, then tidy the cabling.