Sony Betamovie BMC-500p Camcorder...

[19and41]

When I was doing it, I used 12v auto sealed beam bulbs.  They are pretty sturdy.  When a battery had been unused for a long while, we would give them 3 full charge/discharge cycles.

[twocvbloke]

Well the 12v bus bulb I was using was actually quite old and not been that well stored over the years, so, it's not surprising it's given up now... 

I do have a 12v reverse light unit somewhere that I could also use, but I haven't a clue where it is...