AMEC Silent Mode switch box

A: The SB181 houses a simple on-off switch so you can certainly use a on-off toggle switch instead of the SB181 to turn off the transmitter in the CAMINO-108.
The FM radio port on the CAMINO-108 can be connected an FM radio antenna port and it will allow the shared VHF antenna to also act as an FM radio antenna which should significantly enhance reception of your FM radio. Answer provided by:  Doug Miller (3/25/2019)