The beauty of vintage projector bulb filaments with low voltage

[Iain Petrie]

I just fired up a couple of very old (anyone know how old??) projector bulbs from a 1930s/40s Specto 500 9.5mm projector.
With very low voltage from a battery pack the filaments really are beautiful! Now I need to collect more...
Results on my blog here:

https://9point5mm.blogspot.com/2020/...tor-bulbs.html

[Maurice Leakey]

Iain
Yours is not the 500 model. The first Specto projectors came out in 1936 and used the pre-focus A1/3 30volt 100 watt lamp.
The 500 model came out in the 50s and used the A1/7 115volt 500 watt lamp.

Maurice

[Iain Petrie]

Thanks for the correction Maurice. So the 30v lamp I have could be from the 1930s? If so, it's amazing it still works perfectly 80 years on.

[Maurice Leakey]

The pre-war models were black. After the war they were a silver/grey. Yours appears to be the latter. I bought one new in 1950 and that had the 100watt, 30 volt lamp.

Maurice

[Iain Petrie]

Thanks, there's very little information out there online about these old bulbs, it seems!

[Paul Adsett]

When I lived in the UK I worked for several years at the English Electric Valve Company in Chelmsford (now Teledyne e3) where they made electronic tubes, or valves as they are called in England. Electronic tubes are amazing and beautiful devices, so much more interesting, and some say better, than their solid state equivalents. Microwave tubes, such as magnetrons and travelling wave tubes, are in a class of their own in terms of mechanical and electronic intrigue.
Incandescent light bulbs are the most basic form of electron tube, just a filament in a vacuum, but have a beauty of their own that LED lights just do not have. Some of the filaments in vintage light bulbs are truly amazing structures, and there seems to be a re-surgance of these for home and restaurant lighting.
If anyone ever gets to Fort Myers Florida do go to the Thomas Edison winter home and museum where you will find hundreds of filament bulbs, as well as Edison phonographs and Kinetescopes, on display. The most amazing incandescent light bulbs were those used for Lighthouses, some of which are 6ft high!
.

[Iain Petrie]

That's interesting Paul. Tubes / valves are even more of a mystery to me than lamps but I hope to educate myself about all these fascinating devices. Yes, it's the beautiful structures and wide variety which has caught my attention, even though I understand very little about the science and mechanics so far. And yes, there seems to be a massive market for repro antique and vintage filament lighting. I'm searching online for the original ones to buy, but mostly find sites selling modern repro ones. They are often called "antique" or "vintage", making it hard to find ones that really are!
Maurice, speaking of trying to educate myself, I just read this: "General Electric dropped the Mazda trademark in 1945, and ceased licensing the name as well. This cutoff date gives the collector a handy benchmark to use when trying to apply a date of manufacture to a light bulb. Only leftover stock carried the Mazda name on any General Electric or Westinghouse lamp sold after the 1945 cutoff." ( https://oldchristmastreelights.com/t...lamp_story.htm) This seems to mean mine is pre-war even though it has the grey-silver top, or am I missing something? Perhaps the above only applies to normal lighting bulbs rather than specialist projector lamps?