It has been recommended to me to replace my 1984 Oday mast head light with a sealed unit LED to avoid VHF interference. I noticed many offering steaming (225 degrees) and anchor (360) features. I assume I will need to run an added wire for this feature and a switch on the electric panel. I'm not at the boat to be able to see if there a switch labeled like that and I only got the boat last April so have not had a chance to use the lights - they have a short and trip the switch when turned on. Is a steaming light required? Am I likely to have it already in the boat since it was built?
The steaming light is only necessary if you are motoring at night. Most regulations don't call it a steaming light, that's the generic term, you will see them referred to as masthead lights in the catalogs and in the regulations. A popular solution is to have a combination Masthead/Foredeck light. This is a popular one:
https://shop.sailboatowners.com/prod.php?508/Series+25+Combined+Masthead/Foredeck+Light An LED light is not needed for the this application because, the light is only used when motoring and and when the motor is running, the alternator is making the electricity, unless you have an outboard.
At the top of the mast is the white 360 degree anchor light. Because this light will be one over night and drawing down the battery, an LED light is highly desirable. This light is only necessary if you are anchoring out at night.
The masthead/foredeck light will require triplex wire, i.e., 3 wires, one for the masthead light, one for the foredeck light, and a common ground, and 2 switches or circuit breakers. The anchor light only needs 2 wires and one switch.
Running new wires while the mast is down is a pretty easy task and it is a pretty safe bet that the wires in the mast are nearing the end of their life. It would be worth your while to run new wire with proper heat sealed connectors.
As with all things marine, shop around for the best prices. Sailboatowners.com, Defender.com, GenuineDealz.com, and waytekwire.com will have some of the items you are looking for.