George, 
The masthead (steaming) light on my Rhodes (1989) is a Perko model and uses
a festoon type bulb. I replaced incandescent with an LED. They have a
tendency to slip out of the brass mounting clip. Testing can be difficult.
Using a couple of test wires with alligator clips and a 9 volt battery, I
disconnected the deck mount connector and attached the alligator clips to
pins in the plug. If light works, you've got a circuit problem inside the
boat. If it doesn't, lower mast to cradle. You should be able to access lamp
without removing tabernacle pin. This is a good time to convert to LED. I
purchased LEDs for all my nav lights from superbrightleds.com. They're a
fraction of the cost of the Marine dealers. You'll need bulb measurement. I
can provide part no. If you need it, let me know. Note: may not be USCG
approved. 

Hope this helps.



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JP Dempsey
s/v Respite 
Rhodes 22 1989/2005
Marshall,VA
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Sent from: http://rhodes-22.1065344.n5.nabble.com/