I recently acquired a retired obstruction light fixture, and I intend to make it work properly as it once did in service. I personally never worked on such an electrical piece, and the lamps themselves are quite big! I see each one is rated at 620W. From what I can see, these are known as mogul prefocus sockets. Initially, I wanted to find a convert (socket piece to convert to lower wattage), but I have been unsuccessful so far. That said, I have come to the conclusion such converters do not even exist. This is my only theory for now, but I am curious to know from collectors that have exact pieces in their collections if they actually exist.

Thanks!

If talking about prefocused base, I doubt there would be any "converter". The thing is, the other lamp would have to exactly match the light source shape, what would be difficult to handle. Plus these used quite high wattage, what was reliability wise problematic with smaller sockets (due to heat issues)

But I guess you may make one (cut away guts from standard E26 socket and connect it into an E49 base), I don't think you need the piece to be compliant with any regulation governing the beam pattern.
Or you may find some converters on e-shops, but these could be far out of focus...

If you're just looking to make the thing light up go with THESE they are Mogul to medium reducers. You'll be able to fit standard sized lightbulbs in them.


If you'd like to split the wattage roughly in half (620 watts to 300 watts) without having to use reducers go with THESE 300 watt general electric bulbs.

I would guess that your cheapest and easiest solution would be the replace the mogul prefocus sockets with standard  medium base porcelain flanged sockets (available at most hardware stores & home centers) if you're concerned with having the filament centered properly in the lens ,you could mount it on threaded rod to space it wherever you want it for the lamp you decide to use, GOOD LUCK ! as for a flasher, all you will meed is a 120v 30 fpm flasher ( readily available anywhere online) if you shop around, you can get a good deal (I paid $15 for one on eBay)