Raytheon GPS Antenna (rail mount)

rfrye1

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Jun 15, 2004
589
Hunter H376 San Diego
The mushroom shaped rail mount antenna for my (1998?) ST-50 Raytheon system finally succumbed to the UV rays and crumbled. I tried to re-wire a replacement GPS antenna into the existing wiring, and that was a failure (probably my error).
I've searched the Forums, no answers.
Does anyone have a "plug and play" solution?? Technology has changed so much since 1998 I'm wondering if there is even one?
thanks in advance.. Bob
 
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rfrye1

.
Jun 15, 2004
589
Hunter H376 San Diego
Side note, eBay has several....used. I just don't know if a Raymarine 108 antenna is interchangeable with a 125, etc.
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
Hi Bob! The first thing I would do would be to take the now deceased GPS apart and see how it ticks. That is, how many wires. I have read a little about the GPS for the ST50 and found that it has three wires. Red, Black, Yellow. Guessing with standard color code, Red would be +12vdc, Black would be return, and Yellow would be NMEA data. If that is the case, then any GPS antenna that accepts these three wires should work.

I would start with a handheld GPS like a Garmin with NMEA output to see if the ST50 accepts the data. You will have to adjust the data rate to match the ST50. This may be the reason the test antenna failed. If this works, then you can install the handheld in the cabin and wire it to the display. This protects the handheld and GPS does work inside the boat. If this does not work, you might be stuck getting a same fit, form, function Raytheon replacement antenna.

But going back to the basics, tear the old unit apart and see if a generic GPS puck will work.

added - another reason to take it apart is it might still work. Maybe one of the wires failed and that is why it no workee. If it is salvageable, get a waterproof project box and put the guts inside that.