Using the Monitor Key
A monitor key may seem like a simple feature, but there is more than one way to use this key. Ordinarily, you use your monitor key as a courtesy to others who may be using the same frequency, but with different tones. When you monitor a frequency, you are listening to everyone on that frequency, regardless of the tones that they may be using. The monitor function strips away the tone requirement so that you can hear all traffic. Many Icom radios have two levels of monitor. One level will open up the speaker to carrier-level squelch, the squelch level set for your radio. The other monitor function will give you completely open squelch and will be noisy, but you will be able hear any faint traffic on the selected frequency.
Here's how you operate the two different monitor levels. Carrier-Level Squelch Monitoring Press the monitor key until the speaker icon appears on the display. Once you release the monitor key, you will stay in monitor mode until the auto reset timer in the programming times out. When this occurs, the speaker icon will disappear, indicating you are no longer in monitor mode. Open-Squelch Monitoring With this level of monitoring, press and hold the monitor key. When the speaker icon appears on the display, you will hear open squelch noise as long as you hold the key down. Once you release the key, you will be monitoring at carrier level squelch, which will continue until the auto reset timer has timed out.