Fault Phenomenon: Unic spider crane wireless remote control effective range decreased from 50 meters to 5 meters.

Troubleshooting Process:
– Checked antenna: antenna loose.
– Checked environment: high-frequency interference source present on site.
– Checked transmission power: low battery voltage causing reduced power.
– Replaced battery, tightened antenna, avoided interference source.

Root Cause: Low remote control battery voltage and poor antenna contact.

Required Parts: Remote control battery.