Changes between squelch on and off, indicated in the telephony display by ‘SQUELCH’ and squelch off (no indication). When squelch is 'on' the receiver is muted in speech pauses. Squelch is automatically set to "ON" when scanning is activated and to "OFF" when it is deactivated. However, it can be manually set to "ON" or "OFF" while scanning. Also, squelch is automatically set to "OFF" when the RX frequency is changed.

Practise on a MF/HF radio simulator

After switching the MF/HF radio ON, it is necessary to set the receiver squelch to eliminate receiver noise. The Sq button changes between squelch on and off.