Enhance guard zone alarms to have multiple levels

[keesverruijt]

Marcus writes:

We can't make alarms that produce anything that needs to be confirmed or reset to keep normal operation of a navigation system. Ever. For any reason. Many professional manufacturers have managed to make their alarms unusable and dangerous this way, just look at Raymarines AIS alarms on the E-series. Useless.

An alarm should be visible but not intrusive. There is no way to know that this alarm is the most important thing for the mariner in that exact time.

If I remember correctly, disruptive alarms are not allowed in the ECDIS standard, and for a good reason.

If we see this as purely a "I am on a crossing without a boat in sight and need to take a nap" kind of alarm, OK, I can turn it off and never use it. But that would be a pity because it could be very useful in other situations as well.

Ideally, there could be 3 levels to select from

1. Off
2. Normal
3. Audible
4. Intrusive

Normal alarm should be visual only, for example the target becomes red and/or flashes, and/or guard zone flashes. Corresponding to the ECDIS standard for dangerous AIS targets. Audible should be like normal but with a single sound when this state occurs Intrusive should be like we discuss now, something you cant get to shut up without confirming....