There is an option available for the Brookhouse NMEA multiplexer, that
allows testing of any NMEA data value and user-control of 4 signals that
can switch a lights (leds), buzzers or relays.
The following is an excerpt from the documentation:

· Testing of NMEA parameter values and setting or clearing of
externally available control signals. The control signals can be used for
warning lights, alarm buzzers or to drive relays to switch lights or
equipment on/off. There are 4 signals available. NMEA parameter conditions
that can be tested a
(Greater than), (Smaller than) and = (Equal). Signals can be turned on or
off if the condition is "true".




The complete document is he
http://www.brookhouseonline.com/pdf%...nipulation.pdf
If your Raymarine plotter is a C-series or E-series, you may want to have a
look at this:
http://brookhouseonline.com/pdf%20files/Mux_AIS_C.pdf

Wout


"rlojmo" wrote in message
oups.com...
Does anyone have a commercial solution for getting an alram out of the
raymaine chartplotters that can actually be heard. I know they sell
the seatlk to nema converter for this purpose, but I am told this will
not sound an alrm for anchor dragging. I bought the shipmodul
multiplxer but unfortunately this does not have switched outputs. Is
there a nema alarm sentence from the raymarine char plotter?

Bob