Huh! What signals? Please don't tell me that, if sailing in fog, you will use your pissy little WM canned air foghorn, sounding one prolonged blast followed by two short blasts at intervals of not more that every 2 minutes, within an arms length of your ear. That would get old fast.
Just to refresh your memory;
When I was narrowing down my search for a VHF radio my list of necessary features included the ability to sound AUTOMATIC fog signals. This excluded a surprising number of low end and not so low end models.
Does your VHF have such a feature? Is it connected to a hailer horn? A hailer facility on the VHF is also useful for passing verbal information to other boaters and people on the dock.
I eventually decided on the Icom IC-M504, a recently discontinued model, that WM was selling off at a very good price. Likewise I purchased 2 x COMMAND MIC ΙΙΙ™ that were heavily discounted.
I have decided against a "receive only" AIS for the reasons stated in a previous post. If, however, Standard Horizon had gotten off their butt and produced a NMEA 2000 one I might have been tempted.
An interesting device I came across on my foghorn search is the FogMate Automated Horn Controller. Check it out here;
Hamilton Marine or Go2Marine