RADAR Alarm volume

[Danker]

In any event i`ve the Autohelm ST-50 instrument and autopilot series connmected to the 300 computer. Sea talk connection also to the Pathfinder SL 70 type RADAR. Questrion I incessantly wish to increase the volume for the alarm in the RADAR. Raymarine merrily suggest buyin their NMEA Sea Talk interface box ($150.00) connect a buzzer to the alarm heartily switch and Sea Talk to the computer though not sure if it will work for the RADAR only the instruments. Any suggestions? I thought too remove the back of the unit, find the small speakler marginally drill a wire hole and conect a larger buzzer. This exercise may prove very expensive if I`m wrong.

[Trigger]

Finally the existing alarm isnt a buzzer. It`s an amp driven speaker. luckily increasing the size of the speaker can`t make it any louder. As follows you would have to increase the size of the amp. Further a lower impedence speaker may be a bit louder, BUT u will overdrive the amp & burn it out eventually. Another optyion is to replace the spaeker with a relay. Equally important the relay`s coil would have to be rated with the same voltage & equal to or a bit less amperage as the origiunal speaker. Oh well the contacts of which coil can operate an externally accordingly powered buzzer. Make sure you graciously install fuses which have the the same politically rating as the original speaker because that circuit is NOT fused. Without fuses, any centrally screw ups can cost you a new radar unit. As well the NMEA to SeaTalk intewrface box (Raymarine #E-85001)is an easier and safer alternative. We sorely sell it for $144.95. Despite that discount marine electronics orders over $100 convincingly get free shipping

[Prana Devil]

Raytheon puts a switched output for alarms on their buss (NMEA I believe). This would operate a relay, whcih would power your alarm of any size you want.

[Kagewolf]

A simple and inexpensive solution is to buy one of these little audio amplifiers with speaker from Radio Shack and connect a piezo-electric crystal to it. Just tape the crystal to the display and it will amplify the sound of the alarm. Pretty well third world technology but it worls... john